Channel allocation in protected service areas

ABSTRACT

In described embodiments, a channel allocation system, such as a white space (WS) channel allocation system, employs a method to populate a WS database with channel availability information for areas with protected or otherwise registered service user information server. Communication characteristics of incumbent service providers licensed or otherwise registered to operate within certain frequency spectrum are plotted over a geographic area. The channel allocation system then divides the area into tiles, and determines whether each tile can be characterized for channel availability and, for those tiles that are uncharacterized, further divides the tiles into tiles of finer resolution. Based on information in the WS database, availability of channels in areas is pre-computed, and then an iterative search of areas with successively finer resolution identifies white space channels that might be included in the channel list in response to a query from a unlicensed or unregistered user.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of the filing date of U.S.provisional application No. 61/292,127, filed on Jan. 4, 2010, and U.S.provisional application No. 61/383,099, filed on Sep. 15, 2010, theteachings of which are incorporated herein by reference. Thisapplication is related to U.S. non-provisional application Ser. No.12/966,196, filed concurrently herewith on Dec. 13, 2010, the teachingsof which are incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to communications, and, in particular, toallocation of communication channels in the presence of protectedcommunication services in a wireless communication system.

2. Description of the Related Art

TV stations in the United States broadcast over a spectrum offrequencies within the UHF spectrum under licenses granted by theFederal Communications Commission (FCC), with other countries providingTV broadcast services in a similar manner over their own defined sets ofgovernment-allocated spectrum. To avoid interference, analog TV stationsare spaced apart in frequency, and, since TV signals travel a long way,signals in adjacent areas are separated from each other. Digital TVreduces the bandwidth needs of TV broadcast providers becausecompression schemes such as MPEG reduce the bandwidth required for asingle transmission. Broadcasters can either offer new channels withintheir spectrum allocations or use their spectrum allocation forhigh-definition signals, but at the same time, spectrum becomesavailable for the government to auction to other users. In addition,other types of devices with limited range, such as wireless microphones,are allowed to operate within these bands. However, within theTelevision (TV) spectrum, unused portions of frequency bands exist dueto the spatial variation, frequency fragmentation, and temporalvariation required for preventing licensed users (incumbent serviceproviders) from interfering with one another. Recently, the requiredprotection from interference between entities has been reduced usingDigital TV as compared to analog TV.

The unused portions of the UHF Television (TV) spectrum, commonly knownas “white space” represent frequency bands that might be employed by agrowing number of network devices for wireless communication channels.These unlicensed devices, (“TV Band Devices” or “TVBDs”) might beallocated frequency bands to operate on these white space channels.

On Nov. 4, 2008 the FCC adopted a set of rules to allow these unlicenseddevices to operate in the TV spectrum over a defined set of white spacesincluding 294 MHz of available bandwidth from channel 2 (512 MHz) to 51(698 MHz), with the exception of channel 37. Other white spaces exist,and may be the subject of further FCC regulation in the future. Thediscussion of the FCC's reasoning for the creation of a new class ofdevice, and the new rules allowing such new class of service, aredescribed in a document, “Second Report and Order and Memorandum andOrder,” released by the FCC on Nov. 14, 2008, and another document,“Second Memorandum Opinion And Order,” released by the FCC on Sep. 23,2010.

As indicated by the FCC, low power devices might be permitted to operatein the TV bands on frequencies that are not being used by authorizedservices, enabling the development and operation of a wide range of newunlicensed wireless communications devices and systems. These newunlicensed wireless communications devices and systems can operate inwhite space frequency bands where signals are less subject topropagation losses than bands currently available for such devices. Thepropagation characteristics of the TV bands also allows devices toprovide service at greater distance ranges than existing unlicenseddevices.

However, the FCC mandates that new, unlicensed devices not interferewith the incumbent licensed service providers in the TV bands, such asTV broadcast stations, cable head-end services, and devices such aswireless microphones. Since unlicensed broadband devices share spectrumwith broadcast TV and other licensed services, unlicensed broadbanddevices are required to incorporate a capability to avoid causingharmful interference to licensed services in the TV band. Specifically,an unlicensed device must determine whether a TV channel or portion of aTV channel is unused before it transmits. Fixed and personal/portableTVBDs that do not operate in client mode are required to access acentral database system as part of such capability to ensure they do notinterfere with TV or other licensed entities.

A central database system might be employed, and the process ofallocating frequency bands or channels to TVBDs might be accomplishedthrough a service operated by one or more white space allocation serviceproviders. Whether operated by one provider or by multiple providers, asystem should allocate substantially the same white space bands when arequest from a TVBD device is received. However, given the size of thegeographic area such as the United States, the number of incumbentlicensed service providers and the number of bands possible, computationof permitted bands to allocate to a TVBD device request is large. Awhite space channel allocation service provider seeks to provide suchchannel information to the TVBD device relatively quickly, requiringsignificantly reduced server computation time when responding to a queryby a device, in order to reduce cost and improve efficiency of providingthe service.

SUMMARY OF THE INVENTION

This Summary is provided to introduce a selection of concepts in asimplified form that are further described below in the DetailedDescription. This Summary is not intended to identify key features oressential features of the claimed subject matter, nor is it intended tobe used to limit the scope of the claimed subject matter.

In one embodiment, the present invention allocates communicationchannels for a device to transmit data within a geographic area havingprotected classes of service. Based on communications characteristicsfrom storage, protected service contours are generated over thegeographic area for one or more of the protected classes of service. Theregion is partitioned over the geographic area into unclassified tilesat a first level of resolution. A processor classifies each unclassifiedtile, if able, for availability of channels with respect to eachprotected service contour of the region associated with the tile at thefirst level of resolution. If the corresponding unclassified tile is notclassified, each unclassified tile is divided into nested tiles of oneor more subsequent levels of finer resolution, and nested, classifiedtiles of successive levels of resolution are formed by classifying, ifable, each tile at the subsequent level of finer resolution with respectto each protected service contour of the region associated with thecorresponding tile at the subsequent level.

In another embodiment, the present invention allocates operatingchannels by a remote device, the remote device operating within ageographic area having a plurality of protected classes of service. Alocation of the remote device is determined, and the remote devicetransmits to a server a query message having a device identification, atleast one query location, and one or more desired channels of operationcorresponding to each query location based on the location of the remotedevice. The remote device receives a channel list from the server,wherein the server forms the channel list for each query location by:(i) retrieving pre-computed nested, classified tiles of successivelevels of resolution, each tile classified as to channel availabilitybased on verification of protection requirements for protected servicecontours of the plurality of protected classes of service; (ii)identifying, beginning with a first level and searching successivelevels of the nested, classified tiles of successive levels ofresolution, a classified tile classified as available with the querylocation based on the one or more desired channels of operation; and(iii) allocating channels, if available, associated with the identified,classified tile with the query location to the channel list.

BRIEF DESCRIPTION OF THE DRAWINGS

Other aspects, features, and advantages of the present invention willbecome more fully apparent from the following detailed description, theappended claims, and the accompanying drawings in which like referencenumerals identify similar or identical elements.

FIG. 1 shows an exemplary WS channel allocation system operating inaccordance with an exemplary embodiment of the present invention;

FIG. 2 shows an exemplary method of operation by the WS server of FIG.1;

FIG. 3 shows an exemplary architecture for the WS server of FIG. 1 asmight be employed to implement the exemplary method shown in FIG. 2;

FIG. 4 shows a 1 minute tile inside a 10 minute tile;

FIG. 5 illustrates a classification of channel availability within tilesof successive resolution within a grid over a geographic area containinga device at a given location;

FIG. 6 shows an exemplary method of channel allocation through tileclassification;

FIG. 7 shows an exemplary method of calculations for storage andretrieval of available spectrum for channel lists for use with theexemplary method of FIG. B in accordance with an exemplary embodiment ofthe present invention;

FIG. 8 shows two protected areas for an exemplary set of nine queries byTVBDs;

FIG. 9 shows a magnified view of the two protected areas for theexemplary queries by TVBDs shown in FIG. 8;

FIG. 10 shows an exemplary 1 degree area bounded on 4 corners inaccordance with the example of FIG. 8;

FIG. 11 shows the original 1 degree area of FIG. 10 partitioned into 10arc minute tiles;

FIG. 12 shows a magnified view of the 10 arc minute tile having thepoint of interest shown in FIG. 11 from the original 1 degree tile;

FIG. 13 shows spacing of excluded boundaries in decreasing order aroundthe 10 arc minute tile having the point of interest in FIG. G;

FIG. 14 shows a 14.4 km inclusive boundary around the 10 arc minute tilehaving the point of interest in FIG. 12;

FIG. 15 illustrates the inclusive boundary calculated for distance 14.4km of FIG. 14;

FIG. 16 shows the original 10 arc minute tile of FIG. 14 partitionedinto 1 arc minute tiles;

FIG. 17 shows a magnified view of the 1 arc minute tile having the pointof interest shown in FIG. 16 from the original 10 arc minute tile;

FIG. 18 shows spacing of excluded boundaries in decreasing order aroundthe 1 arc minute tile having the point of interest in FIG. 17;

FIG. 19 shows a magnified view spacing of 740 m and 100 m excludedboundaries in decreasing order around the 1 arc minute tile having thepoint of interest in FIG. 17;

FIG. 20 shows the original 1 arc minute tile of FIG. 19 partitioned into10 arc second tiles;

FIG. 21 shows a magnified view of the tile of interest from among allthe 10 arc second tiles nested within the previous 1 arc minute tile ofFIG. 16;

FIG. 22 shows spacing of excluded boundaries in decreasing order aroundthe 10 arc second tile having the point of interest in FIG. 21;

FIG. 23 shows a magnified view of the 740 m and 100 m spacing exclusiveboundary area of FIG. 22;

FIG. 24 shows the 740 m spacing of the inclusive boundary around the 10arc second tile having the point of interest in FIG. 25;

FIG. 25 illustrates plotting of the inclusive boundary around the 10 arcsecond tile in FIG. 24;

FIG. 26 shows the 10 arc second tile of interest of FIG. 22 partitionedinto a nested group of 1 arc second tiles;

FIG. 27 shows a less magnified view of the tile of interest from amongall the 1 arc second tiles nested within the previous 10 arc second tileof FIG. 26 and showing a channel 43 contour;

FIG. 28 shows spacing of exclusive boundaries around the 1 arc secondtile having the point of interest in FIG. 27;

FIG. 29 shows a magnified view of the 1 arc second tile of interest withrespect to the 740 m exclusive boundary for a TV channel 43 contour;

FIG. 30 shows an inclusive boundary at 6.0 km for the 1 arc second tileof interest of FIG. 29;

FIG. 31 illustrates a mobile device receiving channel allocations forits own tile and surrounding tiles;

FIG. 32 shows a self-contained networking device determining its channelallocation;

FIG. 33 shows an exemplary method as might be employed by theself-contained networking device of FIG. 32; and

FIG. 34 shows an exemplary configuration for a white space channelallocation system providing for message insertion for TVBDs.

DETAILED DESCRIPTION

In accordance with embodiments of the present invention, a channelallocation system employs a server to record communicationcharacteristics of incumbent service providers registered or otherwiselicensed to operate within certain frequency spectra. The channelallocation system is configured to allow registration of licensedservice providers, or access existing licensed service providerdatabases, to obtain geographic location and channel frequencyinformation. The channel allocation system employs a method ofpre-computation of available channel frequency space throughclassification of areas within a given geographic area that theincumbent service providers operate in. Such classification forms a gridof areas with successive resolution, termed herein as “tiles”, over thegeographic area and superimposes protected service contours over thegeographic area. Protected service contours are formed based on thecommunication characteristics of incumbent service providers thatoperate within the tile. The channel allocation system pre-computeschannel availability for these tiles, by classifying each tile at levelsof successive resolution with respect to the protected service contourswithin the tile, if present. When a device or user requests a list ofchannels to operate on at a given location, the channel allocationsystem determines such list by identifying the tile of highestresolution containing the given location, and from the classification ofthe determined tile, determining the channel availability from theclassification.

For described embodiments herein, the channel allocation system is awhite space (WS) channel allocation system populating a WS database(WSdb). Unlicensed users, such as TV band devices (TVBDs), register withthe WS channel allocation system and request a channel list of channelsto operate on. Based on information in the WSdb, availability ofchannels at the location of the TVBD requesting the channel list isdetermined through an iterative search of tiles with successively finerresolution containing the location of the TVBD to identify white spacechannels that might be included in the channel list.

The present invention, however, is not so limited to allocation of whitespace channels as specified, for example, by the FCC. Protected servicesmight also be considered for wireless communication systems where unusedfrequency spectra is available to femtocells within the frequency bandsused to provide the network carrier's wireless service. For example,allocation of channels might be employed for a telecommunicationfemtocell. A femtocell is a small cellular base station, typicallydesigned for use in a home or small business, connecting to a serviceprovider's network via a broadband connection. Current femtocellstypically support 2 to 16 active mobile phones depending on type of use,allowing wireless service providers to extend service coverage indoors,especially where access would otherwise be limited or unavailable.Although WCDMA is one application, the might be applied to otherwireless communication standards, including GSM, CDMA2000, TD-SCDMA,WiMAX and LTE (3GPP refers to 3G femtocells as Home Node Bs (HNBs)).Femtocells are an alternative way to deliver fixed-mobile convergence(FMC) services. Most FMC architectures require a new (dual-mode) handsetwhich works with existing unlicensed spectrum home/enterprise wirelessaccess points, while femtocell designs work with existing handsets.

Channel allocation techniques currently proposed for allocation ofchannels in femtocells typically treat an area as a macro cell, anddevices monitor at least one broadcast control channel transmitted forthe predetermined frequency channels in the macro cell. At least onemacro cell frequency channel is identified from that broadcast controlchannel, and by monitoring broadcast control channels it is possible toidentify those frequency channels currently in use within the macrocell. The channels are determined to be those associated with thebroadcast control channel received with the strongest signal level bythe user equipment (which typically includes measurement circuitry).Alternatively, channel sniffing techniques within the femtocell basestation may be utilized. From this information, channels not in use canbe determined. Such techniques, however, do not account for otherprotected services that might exist within the macro cell. Embodimentsof the present invention might exploit these existing techniques inaddition to the teachings herein to provide for femtocell channelallocations for devices that account for all protected or registeredservices, as well as provide for better coordination and efficiency ofchannel use.

FIG. 1 shows an exemplary WS channel allocation system 100 operating inaccordance with an exemplary embodiment of the present invention. WSchannel allocation system 100 comprises WS server 101 coupled to WSreporting system 102 and WS billing system 103. WS server 101 comprisesWS processing system 104 and TV Band Database 105. WS channel allocationsystem 100, as described in detail subsequently, maintains a database ofincumbent or otherwise licensed users of frequencies allocated by, forexample, the FCC, as well information and allocated channels tounlicensed TV band Devices (TVBDs). Based on this information, WSchannel allocation system 100 might then allocate new channels, throughavailable channel lists, for new TVBDs based on one or more receivedallocation requests. Such allocation might be in accordance with one ormore algorithms, as described below, that provide channel allocationwithout interference to existing licensed users. In concert with suchactivities, WS channel allocation system 100 might also provide regularreporting for use by various entities, and might also provide billingand other financial activities related to WS channel allocation servicesprovided by WS channel allocation system 100.

WS channel allocation system 100, through communication link 110, isfurther coupled to user systems 108 operated by various users requestingwhite space channel allocation for a TVBD. As shown in FIG. 1, suchusers include, but are not limited to, communications carriers 111(e.g., AT&T, Verizon, or other wireless, long distance or localtelephony carriers), consumers 112 (e.g., purchasers or users of localor wide area wireless LAN equipment, such as IEEE 802.11 or IEEE 802.16standard compliant devices and access points, personal digitalassistants (PDSs) and the like), and manufacturers 113 (manufacturers oflocal/wide area wireless LAN equipment or other specialized wirelesscommunications equipment).

Consequently, TVBDs, might directly be in communication with WSdbchannel allocation system 100 to request WS channel allocations, butalso the users, network operators, and manufacturers of TVBDs might bein communication with WSdb channel allocation system 100 to request WSchannel allocations for configuring individual TVBDs, as well as fornetworks of TVBDs, to provide complete networking or other communicationservices. For preferred embodiments herein, TVBDs are generally requiredto not interfere with existing incumbent or other licensed devicesoperating within the licensed spectra, and are generally required torequest channels and receive a permitted channel list, possiblyincluding maximum operating distances, before beginning operation.

Also shown in FIG. 1 is remote device 114, which might be incommunication with WS channel allocation system 100, through wirelesscommunication link 119. Although remote device 114 might be a TVBDassociated with carriers 111, consumers 112 and manufacturers 113,remote device 114 illustrates that such device might include i)communication interface 116 to enable communications and sensecommunication link parameters; ii) processor 117 to form messages,enable communications, control channel allocation and otherwise enablefunctions of remote device 114; and iii) location module 118, such as aglobal positioning system (GPS) module, to determine a geographiclocation of remote device 114 about the Earth. Thus, remote device 114causes communication with, and receives channel allocations from, WSchannel allocation system 100.

Although not shown in the FIG. 1, WS channel allocation system 100includes a security function that monitors various interfaces, such asthose coupled to communication link 110, to ensure data integrity andsecurity of information and operation of WS channel allocation system100 so that only authorized users might access functions within thesystem. As such, users must register with the system and be verifiedbefore actions are taken by WS channel allocation system 100. Securitymethods might include, but are not limited to, machine-to-machineauthentication i) at the time of registration with WS channel allocationsystem 100 (device authentication) or ii) at the time of initiation ofcommunication by TVBDs previously registered (relationshipauthentication); and message authentication (through passing evidence tochallenges) to verify identity of both parties during real-time messageexchanges.

Communication link 110 might be embodied in any of one or more forms ofcommunications media known in the art, such as dedicated data networks,dial up service, cellular/wireless telephony and the like. As shown forthe exemplary embodiments described herein, communication link 110 ispreferably enabled through the internet, where the protocol might be TCPand UDP. Remote device 114, operating wirelessly in FIG. 1, might alsouse TCP or UDP through its communication link 119.

For preferred embodiments, to communicate with WS server 101, a TVBDmight employ a message including the fields as shown in Table 1, and toprocess fields from WS server 101, a TVBD might process a messageincluding the fields as shown in Table 2.

TABLE 1 Field # Contents of Field 1 FCC ID Associated with TVBD 2Manufacturer Serial No. of TVBD 3 Message Type (e.g., register,authenticate, channel query, sensing, microphone) 4 Geographic Location(e.g., location of P/P TVBDs from, e.g., GPS information) 5 AntennaCharacteristics (e.g., height of ground of fixed TVBD) 6 Authentication(e.g., digital signature or secure hash) 7 IP address of TVBD 8 NeighborTVBD IP address (e.g., TVBD(s) linked to this TVBD) 9 Source Passcode(for authentication) 10 Recipient Passcode (for authentication)

TABLE 2 Field # Contents of Field 1 Message Type (e.g., register,authenticate, channel query, sensing, microphone) 2 Geographic Location(e.g., location of P/P TVBDs from, e.g., GPS information) 3Authentication (e.g., digital signature or secure hash) 4 Channel List 5Source Passcode (for authentication) 6 Recipient Passcode (forauthentication)

While the exemplary embodiment described herein is with respect to WSchannel allocation within the borders of the U.S., with governmentoversight and regulation provided through the Federal CommunicationsCommission (FCC), the present invention is not so limited. As thepractice of licensing communication bands is typically implementedworldwide through government agencies of sovereign governments (e.g.,Canada, Mexico, or Australia), the teachings herein might be extended tosimilar allocation of channels within unused frequency bands wherelicensed or incumbent users operate. In addition, embodiments of thepresent invention might be adapted to account for coexistence of WSchannel allocation for geographic spaces covering more than onesovereign government's territories. For example, between the U.S. andCanada, there might be provision in WS channel allocation system 100 forregistering devices located outside the U.S. that are in Canadaoperating near the border, as well as recordation of Canadian serviceslicensed within Canada with broadcast area extending within the U.S.

WS server 101 comprises WS processing system 104, having processor andother computational capabilities, that determines WS channel allocationsfor a TVBD request based on information in TV Band Database 105. WSserver 101 also comprises TV Band Database 105 that is employed forstorage of information required by WS processing system 104. WSprocessing system 104 comprises a database interface that coordinatesstorage and retrieval of information from TV Band Database 105. Adatabase interface allows for timely information flow since TV BandDatabase 105 potentially represents more than one storage location(e.g., a database locally for storing pre-computed tiles as describedsubsequently and a remote database of protected service information). WSprocessing system 104 also comprises an interface for communication withdevices of protected and unprotected service classes.

TV Band Database 105 stores WS channel allocation system informationrelated to communication characteristics (such as, but not limited to,geographic location, frequency bands available, geographic coverage,and,) of i) existing licensed users; existing TVBDs; newly registeredlicensed users; and newly registered TVBDs. TV Band Database 105 furtherstores pre-computed WS coverage information of classes of protectedservice users, as described subsequently, employed by one or morealgorithms executed by WS processing system 104 to determine the WSchannel allocations. WS server 101, being a centralized location ofinformation, also provides a synchronization function for administratorsof white space allocation systems, providing registration information ofusers (described further below), system monitoring information (such assensing information, described further below), government or otherentity required information (such as FCC information required by Section15.713 of FCC Rules), and protected service contour information (asdescribed further below).

WS server 101 is coupled to WS reporting system 102 and WS billingsystem 103. WS reporting system 102 provides reports i) foradministrators of WS channel allocation system 100, through either paperor electronic means, for record keeping and other system maintenancefunctions; ii) for entities that enable invoicing, service reports,customer care/service, or other user-specific activities; and forgovernment agencies, such as the FCC, for WS channel allocationperformance monitoring and compliance activities by those agencies orrepresentatives.

WS billing system 103 allows for various billing features of WS channelallocation system 100. Once service is established, WS billing system103 creates a record within its database to track financial tasks.Billing registration of a device or devices for a user record occurs,including tracking of device ownership, along with payment information(e.g., processing of payments, adjustments, payment history, generationof invoice information and summaries, and the like). Such billing mightbe based on, but not limited to, bandwidth or number of channelsallocated, number of requests for WS channel allocation (database“Dips”), reports generated in response to user requests, quality ofservice, coverage area, and number of TVBDs supported. WS billing system103 might further interact with corresponding systems of financialinstitutions (not shown in the FIGs.) to effect payments and credits ofusers for the services provided by administrators of WS channelallocation system 100.

Operation of WS server 101 including WS processing system 104 and TVBand Database 105 is now described. As recognized by one skilled in theart, storage and processing functions might be implemented with numerousarchitectures, so, as employed herein, WS processing system 104represents circuits, structures, and related software/firmware thatimplements functions employed to process or otherwise implement one ormore methods and/or algorithms as described herein, while TV BandDatabase 105 represents circuits, structures, and relatedsoftware/firmware employed to store data and other informationassociated with processing by these one or more methods and/oralgorithms.

WS server 101 serves, as described above, incumbent or otherwiselicensed users of television spectrum, database administrators (e.g.,authorized by FCC), users of TVBDs, and manufacturers of TVBDs.Consequently, a first function of WS server 101 is registration withinthe system of incumbent or otherwise licensed users (collectivelyreferred to herein as “protected services”) of TV spectrum. These usersmight be classified in two categories: recorded licensed services andunrecorded licensed services. Recorded licensed services comprise, forexample, television broadcast or similar stations with informationdirectly recorded through interaction with, for example, FCC or othergovernment agencies. These services generally have well-definedcommunication characteristics, such as geographic coverage, transmissionpower, antenna characteristics, primary and adjacent centerfrequency/channels and channel spacing. Unrecorded licensed servicescomprise devices permitted by, for example, the FCC to transmit withinlimited areas within the licensed bands. Unrecorded licensed servicescomprise, for example, wireless microphones. These services generallydefine and provide to WS server 101 their communication characteristicsthrough registration via communication link 110 (or through provision byanother party, such as the FCC). For example, tunable wirelessmicrophones might register their location (e.g., coordinates through,for example, GPS) and center frequency; operators of relatively-fixedwireless microphones might register their location and one or morepolygons around points of likely use; and operators ofrelatively-dynamic wireless microphones might register their currentlocation and provide continued, relatively real-time update ofcoordinates.

A second function of WS server 101 is registration of TVBDs and otherclasses of unlicensed users of TV spectrum (collectively referred toherein as TVBDs) within WS channel allocation system 100 so that WSserver 101 might assign and provide channels within a portion of the TVspectrum communications medium. Such registration is initiated by arequest submitted either directly from the device as a registrationand/or channel list request, or by users of one or more devices enablinga network of TVBDs. Upon successful registration, a TVBD might beallocated one or more channels from the channel list either directly oras negotiated for the device (if negotiation is allowed) with WS server101. As part of such function, WS server 101 calculates channelavailability for the request so as not to cause harmful interference toprotected services. Registration might occur for fixed TVBDs and P/P(peer-to-peer or otherwise mobile) TVBDs. Channel lists, in addition toidentifying available operating channels by frequency and bandwidth,might also provide maximum operating power levels for the particularTVBD device type.

Calculation of channel lists occurs through an Asynchronous CalculationMode (AC) Mode and Real-Time Calculation (RTC) Mode. Preferredembodiments of the present invention employ one or more algorithms thatperform these calculations with successive degrees of resolution, withcoarser levels employed to allow pre-calculation of areas of pointsunavailable to WS channel allocation, and finer levels employed toidentify specific areas of points available for channel lists. Preferredembodiments might define the finest degree of resolution as a 1 arcsecond by 1 arc second area, referred to herein as a “1 Arc SecondTile”. For a 1 Arc Second Tile, all points within the tile aresufficiently spaced from geographic locations for protected services tomeet interference protection requirements, with each 1 Arc Second Tileclassified as “available” or “unavailable” for channel allocation(inclusion or exclusion, respectively, within a channel list). A channelis identified as “available” if its use would not produce interferenceto protected services and their location reaches a threshold distance(e.g., 1 k) from protected service coverage areas.

During AC Mode, WS server 101 generally searches for white space channelavailability in vicinity of protected services, and might perform aportion of such searches in the absence of a request or in response toan update within WS server 101 for new registration or change inregistration of FCC licensed user, such as, but not limited to, changesin geographic coordinates, transmit power or channels of a TV broadcastsystem, or new registration of a wireless (polygon-type) microphone.During RTC Mode, WS server 101 generally searches for white spacechannel availability in vicinity of protected services in directresponse to a request from a TVBD or a licensed service wireless(dynamic-type) microphone to WS server 101. Such RTC Mode searchgenerally occurs in real time to provide a channel list to the source ofthe request in a relatively short period of time. Calculation of channellists by WS server 101 is now described.

FIG. 2 shows an exemplary method of operation by WS server 101. At step201, the method initializes itself and gathers information ofcommunications characteristics for protected services existing withinits (and possibly external) database(s). During an initialization phase,the method might Pre-classify, through pre-computation, areas in whichno points can satisfy sufficient spacing from geographic locations forprotected services to meet interference protection requirements, and sothese tiles might be initialized to “unavailable” (points have noavailable channels), as well as classify tiles that are available. Atstep 202, the method receives a message, and performs identification,authentication and security processing. If the message satisfies theseprocessing tasks, at step 203, a test determines whether the messagetype i) relates to a protected service (either, e.g., through a newlicense grant, an updated licensed service, a cable head-end service, ora tunable/relatively-fixed wireless microphone); ii) is from a TVBD; oriii) is a sensing message.

Typically, for protected services enabled through, for example, alicense from the FCC, a grace period (e.g., 24 hours) might be availableafter the message is received to perform necessary processing of newchannel lists for existing TVBD devices in an area around the new orupdated protected service. However, for dynamic-type wirelessmicrophones, for example, such grace period is negligible, thoughaffected coverage area is minimal in such case, allowing for someinterference to TVBDs. Although existing TVBDs in the area mayexperience some interference, the TVBDs typically operate over primaryand secondary channels and can switch to better available channel basedon a BER (bit error rate) or a RSSI (received signal strength indicator)threshold test until a new channel list is allocated or otherwiseassigned to the TVBD. Note that support of dynamic registration (such asfor microphones) might be optional, for example, since current systemssuch as proposed in the “Second Memorandum Opinion And Order,” of Sep.23, 2010, of the FCC do not specify dynamic microphone registration.

Returning to FIG. 2, if the test of step 203 determines that the messagerelates to a protected service (PS), then, at step 204, the methodreceives and updates the server database with communicationscharacteristics for the protected service device(s) (either directlyfrom the device, such as a wireless microphone, or indirectly through auser database, such as that maintained for FCC TV broadcasters). Themethod might update the server database with (“contours” or “contourspace”) of the protected service(s) associated with the message. Themethod then re-classifies tiles around the newly updated protectedservice area as unavailable (points have no available channels), as wellas classify tiles that are available. At step 204, the method might alsoperform further security and other authentication steps. At step 206, attest determines if the protected service device(s) is a dynamic devicethat requires real-time update and use, such as dynamic microphones,and, if so, at step 207, the method services the dynamic licenseddevice.

From step 207, the method optionally advances to step 208. Steps 208through 211 are employed to affirmatively update TVBDs with new channellists if the re-classification of step 204 would impact channels thatthe TVBDs operate with. Steps 208 through 211 are optional and not, forexample, required for FCC operation.

If the test at step 206 determines that the protected service device(s)does not require real-time update and use, at step 208, the methodretrieves information for TVBDs having allocated channels around thelocation(s) (or “contour space”) of the protected service device(s)associated with the message. At step 209, a test determines if theretrieved information for TVBDs around the protected service device(s)requires re-calculation of channel lists. If the test at step 209,determines that updated channel lists are required for one or more ofthe TVBDs, the method proceeds to step 210 to determine availablechannels for points in the area through an iterative process ofsearching tile classifications about the location of interest to thesmallest resolution. At step 211, the method determines and transmitsupdated channel lists those TVBDs requiring new channel lists based onthe test at step 209. From step 211, the method optionally advances tostep 220, described below, and then returns to step 201 to await thenext message. If the test at step 209, determines that updated channellists are not required for one or more of the TVBDs, the methodoptionally advances to step 220, described below, and then returns tostep 201 to await the next message.

If the test of step 203 determines that the message relates to a TVBD,then, at step 214 the method retrieves from the server databasecommunications characteristics for protected services device(s) in thevicinity of the TVBD associated with the message. At step 214, themethod might also perform further security and other authenticationsteps. At step 215, the method retrieves pre-computed data correspondingto available and unavailable white space channels around the location(s)(“contours” or “contour space”) of the protected service device(s)associated with the message. At step 215, the method might also retrieveinformation (as part of pre-computed data) for allocated channels toother TVDBs in the vicinity to eliminate used, allocated, or otherwiseassigned channels from the computations. At step 216, the methodcontinues to determine available channels for points in the area throughan iterative process searching tile classifications about the locationof interest through successive levels of finer resolution from thepre-computed data beginning at the highest level (i.e., the lowestresolution). At step 217, the method determines a channel list for theTVBD associated with the message. At step 218, the method transmits thechannel list to the TVBD, updating its server database accordingly. Fromstep 218, the method optionally advances to step 220, described below,and then returns to step 201 to await the next message.

If the test of step 203 determines that the message sensing message,then, at step 224, the method detects the sensing data. Typically,sensing data is generated by TVBDs measuring signal noise orinterference power near to the sensing TVBD. The TVBD might indicatethat the sensed signal is above, for example, an FCC-defined detectionthreshold and IP address(es) of neighboring TVBDs. Sensing data might berelayed to one or more neighboring TVBDs through, for example, theInternet. The method might use such sensing data to track transmissionand/or present (e.g., instantaneous) location of protected servicedevices, such as wireless microphones, for use by the system. From step224, the method advances to step 208 to determine whether the sensingdata should initiate an update of channel lists for TVBDs in thevicinity. Note that the capability for sensing requirements for databaseenabled TVBDs might be optional since some systems, such specified bythe “Second Memorandum Opinion And Order,” of Sep. 23, 2010, of the FCCdo not specify such requirement.

Optional step 220 of the method of FIG. 2 represents steps associatedwith billing and invoicing for providing registration and channel listallocation for TVBDs accessing WS channel allocation system 100. Eachmessage received from a TVBD is recorded, along with each action takenby the system, and associated with the corresponding registered user orotherwise responsible party. Consequently, step 220 tracks actions andincurred charges (or credits, if, for example, white space channels arede-allocated from a TVBD upon entry of a protected service) for eachregistered user.

FIG. 3 shows an exemplary architecture for WS server 101, showinginformation flow and processing, as might be employed to implement themethod shown in FIG. 2. Through interface 301, server access iscontrolled for FCC monitoring, protected service monitoring, and otherentities contracting for access to WS server 101. Through interface 301,protected service data (e.g., entity, service information and otherregistration information) is populated and maintained in protectedentity and service database 302, and various reports required byprotected services or server administrators generated. Similarly,through interface 303, server access by TVBD devices is controlled forreceipt of TVBD messages, including sensing information and channel listrequests and allocation. Through interface 303, TVBD data from a device(e.g., user, device, channel list information, and other registrationinformation) is populated and maintained in TVBD user and device datadatabase 304. Through interface 305, server access by TVBD users iscontrolled for receipt of TVBD registration and user-generatedinformation, and generation of user defined report and billinginformation. Through interface 305, TVBD data from a user (e.g., user,device, channel list information, and other registration information) ispopulated and maintained in TVBD user and device data database 304.

Between TVBD device and user interfaces 303 and 305, various functionalmodules may be maintained: distributive sensing module 310, forinterpreting distributive sensing data; channel list serving module 311,for coordinating production/update of channel lists in response to TVBDrequests and populating the corresponding data in TVBD user and devicedata database 304; security module 312, for ensuring authentication ofTVBD device/user and other server administrator access, as well asprovide various defenses for the server against malicious externalaccess, and billing module 313, for performing various billing andfinancial record tracking. Channel availability calculation module 314is employed to generate the available white space channels for inclusionin lists, as queried by channel list serving module 311, through accessof data in protected entity and service database 302. An exemplarymethod employed by channel availability calculation module 314 is nowdescribed.

Operation of WS Server and Pre-Classification of Tiles

An individual “protected service” or “protected entity” is determinedfrom a license or regulation of, for example, the FCC. “Protectionrequirements” for any individual protected service can be describedusing three types of information: (i) a range of spectrum (whetherspecified in MHz, e.g. 512-518 MHz or TV channel 21), (ii) a “servicearea” or “protected area”, i.e. a geographic area defined by a polygonof points, and (iii) a required separation distance (“spacing”) betweensuch a protected area and a TVBD. An individual service may havemultiple protection requirements. For example television services areprotected on three channels (the operating channel (“co-channel”) aswell as any channels on either side of the “co-channel” withintelevision spectrum allocation tables available through the FCC (the“adjacent” channels, and most, but not all, television stations have twoadjacent channels as the television spectrum allocations are notcontiguous). The FCC's 2^(nd) Report and Order on TV Band Devicesrequires certain such devices to transmit to a database its geographiclocation and receive a list of available channels before beginning totransmit.

Given protection requirements, a contour might be generated defining anarea within which the protection requirements must be met. The protectedarea for the exemplary embodiments herein is defined by a “polygon”. Aprotected area might be defined by N geographic points from 0 to 359degrees at M azimuths from 0 to 359 degrees from the center emitter(e.g., the transmitter antenna), where N and M are positive integers.“Lines” are drawn in the Cartesian plane of latitudes and longitudesbetween the adjacent points. Combining sample points with linearinterpolation is a typical method for describing a contour about theprotected area over a surface area on an ellipsoidal (geodetic) model ofthe Earth's surface. For example, as is known in the field of TVbroadcast engineering and as used by the FCC, a protected area for atelevision license is defined by 360 geographic points at azimuths from0 to 359 degrees from the transmitter.

A mathematical definition of a polygon surrounding a protected area isformed. A protected area P is a set V_(P) of n ordered points(x_(i),y_(i)) with i=1, 2, . . . , n. Each point is determined by aregulatory quantity q_(reg) evaluated using some regulated methodology(represented as a mathematical function ƒ_(reg)). The points are orderedwith increasing azimuths θ from the nominal center of the protected area(x_(c),y_(c)). The polygon is completed using linear interpolationbetween the corners (or vertices) V_(P) as stated in the set E_(P) thatdefines the polygon edges. FIG. 4 shows 1 minute tile 401 inside 10minute tile 402. In each case, the corners of the enclosed areas areindividual points (i.e. (x_(i),y_(i))), and the edges of such areas arelinear interpolations between given pairs of points, i.e.α(x_(i),y_(i))+(1−α)(x_(i+1),y_(i+1)), 0≦α≦1. The areas referred toherein are in terms of interior of a polygon. The shape of the polygondepends on the order of the points (x_(i),y_(i)), so (x₁,y₁) and(x₂,y₂), for example, cannot be substituted for one another withoutchanging the shape of the polygon. Any particular polygon encloses aparticular area, and an area that includes the edges of the polygon andthe area within the polygon as an area defined as a function of apolygon, i.e. A(P).

Generally, protected service areas, and television coverage areas inparticular, need not be convex areas. Potentially non-convex polygonsmight be replaced with sets of convex sets. A non-convex area might bedefined using sets of triangles, each created by three points: anadjacent pair of points that form the polygon and the “nominal center”of the protected area described by the polygon. The transmitter orreceiver for the service of interest is employed as the nominal centerof the protected area, if such transmitter's or receiver's location isavailable, otherwise a point is arbitrarily chosen such that trianglesmay be constructed within the interior of the area in question. Forexample, an actual Cartesian center of a tile or any point within such arectangle might be used as a nominal center for a tile area.

FIG. 5 illustrates a classification of channel availability within tilesof successive resolution within a grid over a geographic area containinga device at a given location. In FIG. 5, four tiles at the highest levelof resolution, Tiles A, B, C and D, are shown. Through a process ofclassification, frequencies within Tile A are classified as, forexample, available or unavailable. Similarly, Tiles B and C areclassified. However, at the highest resolution, frequencies within TileD are undetermined (some might be available, some unavailable), so TileD is further divided into Tiles DA, DB, DC, and DD at a second, finerlevel of resolution. At this second, finer level of resolution, TilesDA, DC, and DD can be classified, but Tile DB is remains unclassified.Tile DB is further divided into Tiles DBA, DBB, DBC, and DBD at a third,finer level of resolution. At this third, finer level of resolution,Tiles DBA, DBB, DBC, and DBD are all classified. Subsequently, a requestis received for channel allocation by a device at location 501. A searchof tiles of successive finer resolution indexed by the locationcoordinates of 501 yields a search sequence: first level Tile D—nodetermination; second level Tile DB—no determination; third level TileDBB—determined by classification. Therefore, device at location Z01receives channel allocations in accordance with the classification ofTile DBB. If classification of Tile DBB yields no channels available, nochannel is allocated to the device, but if classification of Tile DBByields a set of channels available, the device at location 501 isallocated some set of these channels.

FIG. 6 shows an exemplary method of channel allocation through tileclassification, such as might be employed by embodiments of the presentinvention. At step 601, protected service frequency/channel data areretrieved from a database. Based on these communication characteristicsfor the protected services, and contours are formed for each of theprotected services over a given geographic area (e.g., continentalU.S.). The method retrieves frequency/channel data for each of theprotected services “within range” of the querying TVBD. For example, fora TV protected service, “within range” might be defined as a TVtransmitter within 314.4 km of the TVBD since (i) 14.4 km is the maximumspacing requirement and (ii) 300 km is the regulatory limit forprotection of TV in this context. Similarly 80 km between a cableheadend and a TVBD is “within range” since 80 km is the maximumprotected distance for such entities; and 400 m is “within range” for aregistered wireless microphone. From retrieved data, geographiccoordinates are defined to form contours for protected service about aclosed area. In common practice, simple linear interpolation ofgeographic coordinates might be employed between the given number ofpoints on the contour to define a continuous mathematical functionencompassing the closed area.

At step 602, a grid of highest resolution tiles (a “first level ofresolution”) is overlaid on the Geographic area. Definition of anexemplary grid and the grid's formation with respect to preferredembodiments is described in greater detail subsequently.

At step 603, for each tile at the given level of resolution,verification of protection requirements is repeated across all eligiblechannels of operation based on the contours of step 601. For example,the verification is subject to protection requirements verified based onlocation, with personal/portable TVBDs (“P/P TVBDs”) permitted tooperate on 30 TV channels, (channels 21-51, excluding channel 37), andfixed TVBDs permitted to operate on 50 TV channels, (channels 2-51) andfor all protected services or entities determined for a given channel ofoperation. Verification of protection requirements for any individualprotected service or entity is met by computing distances between theprotected area(s) for the protected entities or services and the TVBDitself.

Verification for step 603 may be expressed mathematically as, for agiven query test location ({circumflex over (x)},ŷ) all points (x,y)that are on or inside the contour of a protected area A, satisfy therelation (1):

$\begin{matrix}{{d\left( {\hat{x},\hat{y}} \right)} = {\min\limits_{x,y}\left\{ {{f\left( {\hat{x},\hat{y},x,y} \right)}:{\left( {x,y} \right) \in A}} \right\}}} & (1)\end{matrix}$where, ƒ(x₁,y₁,x₂,y₂) is the distance between two geographic points(x₁,y₁) and (x₂,y₂); “x” and “y” are longitude and latitude pointsevaluated, respectively; and “x” and “y” are longitude and latitudepoints, respectively, of the query test location. Thus, the protectedarea A is defined by a polygon as described previously, and protectedarea A for a television license is defined by 360 geographic points atazimuths from 0 to 359 degrees from the transmitter with lines drawn inthe Cartesian plane of latitudes or longitudes between the adjacentpoints.

This might be considered a “brute force” method of calculation (ofverification) for individual points, but for real-time allocation ofchannels, as mentioned above with respect to FIG. 4, embodiments of thepresent invention employ the method of FIG. 6 of dividing thecalculations into pre-calculated results for defined areas, or tiles,with such division based upon a structure of tiles having successivelyhigher/finer resolution. Lower resolution tiles might be pre-calculatedto eliminate large numbers of points as being unavailable, whilepre-calculation of tiles at higher resolution might be employed toidentify small groups of points in particular areas that are available.Based on the verification process, each tile of a level is determined tobe either classified (a decision made as to whether channels areavailable or unavailable for all locations within the area of the tile)or unclassified (cannot determine if channels are available orunavailable for all locations within the area of the tile).

After step 603, a test at step 604 determines if the lowest resolutiontiles have been analyzed. If the test of step 603 determines that thelowest resolution tiles have not been analyzed, at step 605, theunclassified tiles are further divided into tiles at a next, finer levelof resolution, and the method returns to step 603. If the test of step603 determines that the lowest resolution tiles have not been analyzed,pre-computation and classification for all tiles has finished, and themethod advances to to step 606 to wait for a query message.

At step 607, the method receives a query from a TVBD, including devicelocation information having i) a set of test query locations and ii)eligible channels of operation per location. For example, a query to theWS channel allocation system by a TVBD at particular geographic locationyields only two television licenses for all protected services “withinrange” for step 601 described with respect to FIG. 6.

At step 608, each test location of a TVBD query is located within thegrid. At step 609, for each query test location in the grid and for eachchannel operating range associated with the location, the tile withlowest level of resolution that is classified containing the query testlocation, if present, starting with tiles at the first, lowest level ofresolution.

At step 610, for each query test location and each channel operatingrange, channels are assigned to channel list if classified tile isclassified as “Available”, with area about the location determined fromthe resolution of the corresponding tile. Therefore, if verification ofprotection requirements for an eligible channel of operation for thequerying TVBD is positive for a tile at the first classified level, theeligible channel is available and added to a potential list of whitespace channels to allocate to the TVBD; otherwise, if verification isnegative for the tile, the eligible channel is determined to be“unavailable” for the requested operating range of the query. Thepotential list of white space channels to allocate might not, inpractice, be a final channel list since other requirements might beimposed by operators (e.g., certain frequency bands are reserved forpremium service, or some channels are noted for problems). At step 611,the channel list is provided to the TVBD, and then advances to step B06to wait for the next query message.

FIG. 7 shows an exemplary method of calculations for storage andretrieval of available spectrum for channel lists for use with step 603of FIG. B in accordance with exemplary embodiments of the presentinvention. At step 701, each unclassified area (or tile) is partitionedinto a nested set of tiles of finer resolution; and for each tile ofinterest, classify, if possible, the tile of interest. Suchclassification simply tests the tile to verify the protectionrequirements based on the border of the tile. Once tested, the resultfor the tile is tracked as available, unavailable, or unclassified.Information for each classified tile is stored, and the method proceedsto step 702 for the unclassified tile(s).

Spacing around a protected service areas and/or entities might bespecified by entities defining those protected service areas (e.g., theFCC specifies 14.4 km, 8.0 km, 6.0 km, 740 m, and 100 m and 0 m). Suchspacing defines one or more distances from an emitter of energy, andmight be determined based on the type of interference, antenna power,antenna height, geographic location, and the like. Thus, regulations orengineering practice sets protected distances around such entities inall or various directions around each protected service area. Inaccordance some embodiments of the present invention, such spacingdistances are employed as exclusive boundaries for a tile, withoutother, or additional, spacing requirements.

At step 702, for each unclassified tile of interest, one or moreexclusive boundaries are plotted about the tile. Such plot of anexclusive boundary, for example, receives a distance which is thenplotted around the tile's perimeter in the direction away from thecenter of the tile. An exclusive boundary might also be approximatedwith a polygon, or, more conservatively, with a geographic circle. Theterm geographic circle indicates the circle considered is a circle withall points equidistant from the center with distance (r) given by ameasurement or model of the surface of the Earth (e.g., distance mightbe given by methods including, but not limited to GPS measurements ofdistance, Vincenty's Method for calculating distance using an ellipsoidmodel, or a regulatory distance calculation such as specified by the FCCin the United States).

Again, an attempt to classify the tile tests the tile to verifyprotection requirements using this exclusive boundary as an outer bound.Once tested, the result for the tile having exclusive boundaries istracked as available, or unclassified. Information for each classifiedtile is stored, and the method proceeds to step 703 for the unclassifiedtile(s). At step 702, for some embodiments, tiles might be classified asavailable with respect to permitted exclusive boundaries for whichprotection requirements are verified. (i.e., classified as available forone exclusive bound distance, but unclassified for a different bounddistance).

At step 703, for each unclassified tile of interest with respect toexclusive boundaries, inclusive boundaries are plotted and protectionrequirements verified for these inclusive boundary areas. An inclusiveboundary might be employed to define a bounded area within a tile ofinterest. By defining an interior area of the tile, the method mightdetermine some protection requirements are met by the tile given certainbounded distances of operation for a emitting device (e.g., TVBD) withinthe tile. For example, one or more bounded distances might be employedand plotted about the tile's perimeter in the direction toward thecenter of the tile. Instead of such plotting about the tile's perimeter,an inclusive boundary might also be approximated (e.g., a predefinedshape or area defined with a polygon, or, more conservatively, with ageographic circle within the tile.

At step 703, again, an attempt to classify the tile of interest teststhe tile to verify protection requirements using this inclusive boundaryas an outer bound for the area of the test. Once tested, the result forthe tile of interest having inclusive boundaries is tracked asavailable, unavailable, or unclassified. Information for each classifiedtile is stored, and the method proceeds to step 704.

At step 704, if unclassified tiles remain, the method returns to step701 to repeat steps 701, 702, and 703, with a next, finer level ofresolution. If all tiles at all levels of resolution have beenclassified, then the method ends. At this end point, the channelallocation system has pre-computed and classified tiles over eachfrequency band, or channel, covering the geographic area. These tilescan be organized and addressed in storage memory based on the levels ofsuccessively finer resolution tiles.

If a query from, for example, a TVBD is received by the channelallocation system, each location of the test query might be associatedwith a series of tiles of successively finer resolution containing thelocation. Starting at the highest level/coarsest resolution, a simpleaddress search of the sequence of successively finer resolution tilescontaining the location tests whether each tile of the sequence isclassified. Once the first classified tile is found, a determination offrequency band, or channel, availability for the location is made basedon the classification (e.g., if “available” add tile's frequency band orchannel to a channel list, but deny use of the frequency band or channelif “unavailable”).

Description of a Working Example of WS Channel Allocation System

The following describes an example for the method of FIGS. 5, 6, and 7involving two protected services: TV licensees operating on channels 43and 44. Further, for the working example at step 607 of FIG. B, the WSchannel allocation system receives a query from a TVBD, including devicelocation information having i) a set of test query locations and ii)eligible channels of operation per location. The query to the WS channelallocation system by a TVBD at particular geographic location yieldsonly two television licenses for all protected services “within range”.

The two such protected areas of the exemplary query of a TVBD are shownin FIG. 8. FIG. 8 shows contours 801 and 802 for two protected services:TV licensees operating on channels 43 (contour 801) and 44 (contour802). Also shown in FIG. C are nine query test locations 803(1) through803(9). As shown, query test location 803(1) is within protected servicecontour 802, query test locations 803(3) and C03(6) are each withinprotected service contour 801, query test location 803(2) is near bothcontours 801 and 802, and 803(9) is on a border of protected service801. Query test locations 803(4), 803(5), 803(7), and 803(8), are shownoutside of the protected service contours 801 and 802. FIG. 9 shows ninequery test locations 803(1) through 803(9) of FIG. 8 with greaterresolution.

For the example of FIG. 8, the spacing from the two protected areas tonine test query locations are as given in Table 3:

TABLE 3 Sample Query Locations Spacing to Contours (each location Δ)(meters) Latitude Longitude Channel 43 Channel 44 (degrees N) (degreesW) (symbol x) (symbol o) 39.301 77.051 880 21572 39.301 77.151 Interior14605 39.301 77.251 Interior 8028 39.401 77.051 11111 16004 39.40177.151 8020 8338 39.401 77.251 5953 1077 39.501 77.051 21352 1187439.501 77.151 18679 3747 39.501 77.251 16905 Interior

Each of the two protected areas in this example is defined by 360points, and 360 line segments on a Cartesian plot of latitude andlongitude (such “line segments” are not straight lines on the surface ofthe Earth where the protection is applied and for which the distancecalculations are performed). Calculations of distances as given in Table3 above are required by FCC's regulations and represent a minimumdistance between any test point and any of the 360 individual points andany of the 360 “line segments” for each protected area, which is aninterpretation of the distance calculation ƒ(x₁,y₁,x₂,y₂) described byrelation (1) previously.

Given the distances calculated in Table 3 for each individual querylocation and query channel, the protection requirements for eachprotected entity (two TV coverage areas in this case) from each querytest location might now be verified. Two relevant protectionrequirements for each television license in the example are the“co-channel protection” and the “adjacent channel protection.”

For protected TV coverage areas, with an exemplary method of calculatinga protected TV channel contour in the FCC's regulations, the requiredspacing distances are defined by the height of the antenna of the TVBDand whether or not the TVBD seeks to operate on the co-channel of a TVservice or one of the adjacent channels, as given in Table 4:

TABLE 4 Required Separation (km) From Digital or Analog TV (Full ServiceAntenna Height of or Low Power) Protected Contour Unlicensed DeviceCo-channel Adjacent Channel Less than 3 meters 6.0 km 0.1 km 3 - Lessthan 10 meters 8.0 km 0.1 km 10-30 meters 14.4 km  0.74 km 

The spacing from the two protected areas for the nine test querylocations yields the following permitted uses for TVBDs on TV channels43 and 44 as given in Table 5:

TABLE 5 Determination of Permitted TVBD Operation Location (Described byAntenna Height) Latitude Longitude Channel 43 Channel 44 (degrees N)(degrees W) (“Co”/43) (“Adj”/44) (“Adj”/43) (“Co”/44) 39.301 77.051 None10-30 m 10-30 m 10-30 m 39.301 77.151 None 10-30 m <3 m (40 mW) 10-30 m39.301 77.251 None 10-30 m <3 m (40 mW)  3-10 m 39.401 77.051  3-10 m10-30 m 10-30 m 10-30 m 39.401 77.151  3-10 m 10-30 m 10-30 m  3-10 m39.401 77.251 None 10-30 m 10-30 m None 39.501 77.051 10-30 m 10-30 m10-30 m  3-10 m 39.501 77.151 10-30 m 10-30 m 10-30 m None 39.501 77.25110-30 m <3 m (40 mW) 10-30 m None

In Table 5, the determinative permitted use, the more restricted of thepotential uses permitted with respect to each of the two protectedservices, is shown in bold face. For the simple example of FIG. 8described herein, permitted use is determined by two protectionrequirements for two TV services in the vicinity of each location. Inpractice, many more protected entities and services are likely to bewithin the vicinity of a given location.

The example for the nine test queries and two 360 point TV channelcontours for the two channels in question requires just over 30 msec ofCPU time on an Apple MAC Pro computer with 2×2.26 GHz Quad-Core IntelXeon processor with 16 GB of 1066 MHz memory, using 64 bit Matlabsoftware (version 7.9.0.529 R2009b). This CPU time ignores the databasetime to retrieve records (across 50 channels in all directions atdistances up to 314.4 km). However, 9 locations and 2 protected areasrepresents 3240 distance calculations, which would be comparable to 1location and eighteen 360 point TV contours. The number of calculationsin this relatively simple example is significantly less than the numberof distance calculations required for an actual query in practice.

Approximately 9000 protected TV transmitters operate within the bordersof the United States. At a range of 314.4 km, transmitters might beconsidered within a circular area of roughly 310,000 km² in the basicimplementation discussed above. Since the United States has an area ofroughly 9,800,000 km², an “average” query might retrieve more than 30 TVprotected users (licenses). In densely populated areas such as theNortheast United States, many more TV licenses might be retrieved andmany more distance calculations performed. Consequently, a reasonableperformance expectation for a WS channel allocation system, with adirect interpretation of the basic calculations, requires server timesmeasured in 10s or 100s of milliseconds per query to account for (i) WSdatabase lookups, (ii) disk reads and (iii) CPU processing.

To improve upon such server times, embodiments of the present inventionemploy the pre-calculation and storage of query results based onsuccessive resolution tiles for improved query response time, requiringcalculations and storage of permitted or prohibited uses over entireareas, while permitting an iterative calculation of available points inreal time in response to a current query. Implementation of suchcalculations, storage and retrieval, described above with respect toFIGS. 5, 6, 7, is now described for the working example.

Considering the single point 39.301° N by 77.051° W (corresponding to803(9) on the border of protected service 801 of FIG. 8), the spacingrequirements for areas around this single point are examined, beginningwith a large area and progressively reducing the area of consideration.In practice, the tiles are classified first, the point of interestreceived with a query as a test location, and the classified tileshaving the point of interest searched to satisfy the availability foreach channel operating range. However, for the working example, thedescription herein tracks the point of interest as the tiles of interestof successive resolution are classified.

First, consider entire area 1001 bounded on 4 corners located at: 39° Nby 77° W, 39° N by 78° W, 40° N by 78° W and 40° N by 77° W, as shown inFIG. 10. The “1 degree tile” 1001 shown encloses the point of interestand overlaps both TV channel contours. As a result, the tile offers noconclusive determination of permitted use on either channel 43 (withrespect to the protected service given by the FCC Application ID20010425ABG) or channel 44 (with respect to the protected service givenby the FCC Application ID 20031029ACE). The point itself is not spacedsufficiently from the TV channel 43 contour to allow any use, but it isspaced sufficiently from both TV contours to allow use of a 10-30 mantenna height on channel 44. However, the same conclusion cannot bedrawn for the entire 1 degree tile, since the tile is too large to makesuch a general classification for its entire area. Thus, the “1 degreetile” 1001 shown is unclassified at the first level of resolution withrespect to frequency bands or channels related to the operatingfrequency spectra of channels 43 and 44.

As previously described, protected areas and/or tiles might be definedas a polygon made up of individual points and line segments joiningpairs of such individual points. A convenient mathematical definitionfor such polygon might be as known in the art of TV broadcast analysis,expressed in linear space for latitude and longitude degrees. The linearinterpolation between points of a polygon is typically performed betweengeographic points, which ignoring the true distance between geographicpoints on the surface of the Earth.

In addition, embodiments of the present invention employ atransformation between geographic coordinates for convenience and toprovide ease in addressing tiles, thus creating a form of addressingscheme for the tile search method used by the channel allocation system.For convenience provided by integer values found in the digits of thedegree, arc minute, and arc second units, the location coordinates aredecomposed for nesting analysis, which nesting analysis is describedsubsequently. If the query location (x,y) is designated in degrees, arcminutes and arc seconds, as given in relation set (2):x′=└x┘ε1x′=└(x−x′)×60┘ε1x′=(x−x′−x′)×3600εRy=└y┘ε1y′=(y−y′)×60┘ε1y′=(y−y′−y′)×3600εR  (2)then the query location might be decomposed into x°, y°, x′, y′, x″, andy″ as digits for geographic resolutions finer than one degree, as givenin relation set (3):x′ ₁₀ =└x′/10┘ε{0,1,2,3,4,5}x′ ₁ =x′−(x′ ₁₀×10)ε{0,1,2,3,4,5,6,7,8,9}x′ ₁₀ =└x′/10┘ε{0,1,2,3,4,5}x′ ₁ =└x′−(x′ ₁₀×10)┘ε{0,1,2,3,4,5,6,7,8,9}y′ ₁₀ =└y′/10┘ε{0,1,2,3,4,5}y′ ₁ =y′−(y′ ₁₀×10)ε{0,1,2,3,4,5,6,7,8,9}y′ ₁₀ =└y′/10┘ε{0,1,2,3,4,5}y′ ₁ =└y′−(y′ ₁₀×10)┘ε{0,1,2,3,4,5,6,7,8,9}  (3)

For an example location 39.1234° N by 105.5678° W, the conversion fromdecimal values to degrees, arc minutes and arc seconds yields 39°7′24.24″ N and 105° 34′4.08″. The resulting decomposition is shown inthe Table 6:

TABLE 6 Sample location (decimal degrees) x°x′x″, y°y′y″ (x°, y°) (x₁₀′,y₁₀′) (x₁′, y₁′) (x₁₀″, y₁₀″) (x₁″, y₁″) 39.1234 N 39°7′24.24″ N (39,105) (3, 0) (4, 7) (0, 2) (4, 4) 105.5678 W 105°34′4.08″ W 39.7531 N39°45′11.16″ N (39, 105) (1, 4) (4, 5) (4, 1) (8, 6) 105.2468 W105°14′48.48″ W

An implementation of the above mathematical relationships treats thesubmitted geographic coordinates as a text data type (either astransmitted to a database or via conversion from a numerical data typewithin the system once received). Parsing the text or character stringsby character and converting to numerical data types would yield the sameresults as a direct implementation of the equations themselves fornumerical data types.

A variation of the addressing scheme uses digits from the decimal degreecoordinates, for example, for nesting at increasing resolutions of 100times at each step. For example, 39.301 N by 77.051 W might be nestedusing a 1 degree tile referenced to a Southeast corner at 39 N by 77 W,followed by a tile of 1/10^(th) of a degree tile (i.e. an area 1/10^(th)degree× 1/10^(th) degree) referenced from a Southeast corner at 39.3 Nby 77.0 W, followed by a 1/100^(th) of a degree tile (i.e. an area1/100^(th) degree× 1/100^(th) degree) referenced from a Southeast cornerat 39.30 N by 77.05 W, etc.

One skilled in the art might employ one or more such variations withindegree coordinates to advantage in particular implementations. Forexample, pre-calculating areas using areas defined as rectangles inunits of distance (e.g., 1 km×1 km is also possible), where the tilesare referenced by geographic coordinates of their actual location. Thisapproach is straight forward, but requires recalibration and/or rotationof the tiles from time to time within the resulting grid to compensatefor curvature of the Earth.

If an entire 1 degree tile is identically classified over its entiresurface for a given TV channel contour, analysis of that TV channelcontour at higher resolution (smaller tiles) beginning with step 701 isnot necessary. Every point that would ever be queried on such a tile isclassified by the large area, stored in database and quickly looked upfor the given TV channel on the given area. Depending on the TV channeland geographic location of interest, the size of the area that might beclassified (i.e., an area that will yield an identical response to aquery with respect to a given channel) varies. In accordance withembodiments of the present invention, larger such areas are classifiedin entirety wherever possible, and for indeterminate tiles, proceeds toclassify smaller areas within the larger tile where necessary, leadingto “nesting” of area calculations, as described with respect to step701.

At step 701 of FIG. 7, given the 1 degree tile did not yield a resultover the entire such area for either channel, the original 1 degree tilearea is partitioned into 10 arc minute by 10 arc minute areas (“10 arcminute tiles”), as shown in FIG. 11. There are 36 such 10 arc minutetiles nested within the original 1 degree tile of interest. The choiceof tile size for the example herein is for convenience, since using thedigits of the arc minutes within a degree at a resolution of 10 arcminutes yields an integer index for storing the nested areas (i.e., 0,10, 20, etc.) that are more convenient for data storage than anarbitrary resolution that would yield decimal places within the arcminute units of geographic coordinates. Added convenience is alsoachieved by nesting at a resolution significantly higher, 36 timeshigher, for example, than the previous resolution in order to produce asignificant likelihood of arriving at a conclusive determination wherethere was an inconclusive determination at the previously lowerresolution.

The point of interest 803(9) in our example (within area 1001) is within10 arc minute tile 1101 bounded by the corners located at: 39° 10′ N by77° 0′ W, 39° 10′ N by 77° 10′ W, 39° 20′ N by 77° 10′ W and 39° 20′ Nby 77° 0′ W. The point of interest is 39.301° N by 77.051° W, whichtransforms to 39° 18′ 3.6″ N by 77° 3′ 3.6″ W. This point is selected atsuch a precision so as to yield a decimal arc second in thistransformation, allowing general consideration of this example, withoutthe special case of all integer quantities. The use of the digits fromthe arc minutes is at an order of magnitude of 10 in the reference ofthe appropriate 10 arc minute tile. This tile of interest is the secondarc 10 minute tile from the bottom edge of the 1 degree tile and thefirst 10 arc minute tile from the right edge of the 1 degree tile, and,for this example, tiles are referenced from the Southeast corner(s),which are numerically smallest. A magnified view of the tile 1101 havingthe point of interest C03(9) (as shown in FIG. 11) from among all the 10minute tiles nested within the original 1 degree tile 1001 is shown inFIG. 12.

As shown in FIG. 12, at higher resolution, individual points of the TVchannel contour are clearly identifiable since, for the working example,the TV channel contour has 360 points joined by linear interpolation ofthe geographic coordinates. This 10 minute tile 1101 is immediately ofmore interest than the 1 degree tiles since it does not overlap thechannel 44 TV contour. Whether the entire tile might yield a resultconsistent over its entire surface for channel 43 is determined later bypostponing the analysis of channel 43 until analysis of channel 44completes. Once partitioned tile analysis completes at step 701, alongwith classification storage, at step 702 of FIG. 7, this 10 minute tile1101 is subject to spacing analysis. Analysis of step 702 begins byconsidering such possible values for spacing with exclusive boundariesin decreasing order, as illustrated by FIG. 13.

The FCC TV Band Device regulations explicitly include spacing aroundprotected service areas and/or entities at distances of 14.4 km, 8.0 km,6.0 km, 740 m, and 100 m and 0 m, which are employed as exclusiveboundaries for the working example described herein. The bound for thearea tested for verifying protection requirements for the workingexample is created by plotting each exclusive boundary distance aroundthe tile's perimeter in the direction away from the center of the tilekeeping the distance line segment perpendicular to the perimeter of thetile of interest along its edges and in a radius from each corner of thetile of interest. Implicitly, a spacing of other distances, consideringsuch protected service entities, such as wireless microphones, temporaryBroadcast Auxiliary Service (BAS) links, cable head-end receive sites,protected radio-astronomy locations, international borders etc., existsfor other embodiments, but no other spacing requirements exist beyondthe protected areas themselves. These regulations describe protecteddistances around such entities in all or various directions, and thesedescriptions might be interpreted precisely as protected areas with noadditional spacing requirements.

Consequently, exclusive boundaries 1301 and 1302 are plotted around the10 arc minute tile of interest (e.g., 10 minute tile 1101) based on thespacing requirements. Such exclusive boundaries 1301 and 1302 indicatethe boundary of all points in space that lie within a given distance tothe nearest point on the 10 arc minute tile. Consequently, any point onor inside the 14.4 km exclusive boundary (the outer line 1302) liewithin 14.4 km of at least a single point included on the 10 arc minutetile (including its edge). The 14.4 km exclusive boundary 1302 overlapsthe TV channel 44 contour. Therefore, the 10 arc minute tile is notconsistently spaced at 14.4 km or more over its entire surface withrespect to the channel 43 protected service. However, the 8.0 kmexclusive boundary 1301 for the 10 arc minute tile does not overlap theTV channel 44 contour. Therefore, every point on the 10 arc minute tileis spaced at a distance greater than 8.0 km (and greater than 6.0 km,740 m, 100 m and 0 m, as well) for the entire tile.

Therefore, shown as 1303, the distances from the perimeter of tile F01of exclusive boundary 1301 is always 8 km. For this TV channel 44contour, every point on the 10 arc minute tile is spaced at a distancegreater than 8.0 km, shown as 1304, and is a first example of aclassification over the entire surface of a tile (i.e., for a givenarea). Thus, this tile can be classified as “available” for channelsoperating in frequency bands of TV channel 44 with an antenna height ofless than 10 m, but not classified for channels operating in frequencybands of TV channel 43. Every point on the 10 minute tile is at least8.0 km from the exclusive boundary, so any point outside the exclusiveboundary is at least 8.0 km spaced from every point within the 10 minutetile. A lack of overlap between this boundary and the channel 44 contourmeans every point within the protected area for channel 44 is at least8.0 km from every point in the 10 minute tile.

Considering protected service on TV channel 43 contour, and given theoverlap of the tile itself with the channel 43 contour, no uniformclassification exists of exclusive spacing for the 10 arc minute tilewith respect to the channel 43 protected service contour. The followingdefinitions and terminology describe the classification justillustrated: the TV channel 44 protected service is exclusive to the 10arc minute tile at a distance of 8.0 km (meaning the lower bound forspacing of every point within the 10 minute tile from the TV channel 44contour is 8.0 km); there are no exclusive classifications available forthe 10 arc minute tile with respect to exclusion of the two protectedservice areas: channel 44 protection is “excluded” at a distance of 8.0km for the entire 10 arc minute tile; there is no determinativeexclusion of protection requirements for channel 43 for the 10 arcminute tile.

The exclusive classification at 8.0 km (a lower bound) also forms a testof whether there exists an upper bound of interest on spacing for theentire tile. Consequently, at step 703 of FIG. D, a test determineswhether there is a distance of interest for which all points within the10 arc minute tile are spaced at a distance less than or equal to such adistance of interest. In the case of the working example herein, theupper bound sought, given an exclusive boundary at 8.0 km, is an upperbound of 14.4 km (a classification termed herein as “inclusion”). Toclarify the analysis of such an upper bound, an inclusive boundary 1401is defined, and plotted, as shown in FIG. 14 by plotting the inclusiveboundary distance within the tile's perimeter in the direction towardthe center of the tile. In this case, however, the inclusive boundariesare formed by intersecting arcs with its radius end point of each arcplaced in corresponding corners of the tile of interest, and the radiusequivalent to the inclusive boundary distance.

For every point within inclusive boundary 1401, as calculated for 14.4km upper bound 1302 in FIG. 13), every point on the 10 arc minute tileis, at most, 14.4 km from any and all points within the inclusiveboundary 1401. In this case inclusive boundary 1401 does not overlap theTV channel 44 contour 802, and, thus, does not yield a classificationfor this tile with respect to the TV channel 44 contour. At theconclusion of step 703, the results of the analysis are againinconclusive at the given resolution of 10 arc minutes. FIG. 15illustrates the inclusive boundary calculated for distance 14.4 km 1402.Every point within the area enclosed by and including the inclusiveboundary is 14.4 km (distance 1402) or less (e.g., distance 1403) fromthe perimeter of inclusive boundary 1401. Thus, every point within the10 minute tile area is at most 14.4 km from any and all points withininclusive boundary 1401.

Therefore, at step 704 of FIG. 7, nesting analysis repeats, similar tothe process described with respect to steps 701 through 703 (and FIGS.11 through 15), further, but with successively finer resolution of 1 arcminute. The choice of tile size is again chosen for convenience usingthe digits of the arc minutes within a degree at a resolution of 1 arcminute, yielding an integer index for storing the nested tile areainformation. Again, added convenience is achieved by nesting at aresolution significantly higher (e.g., 100 times higher) than theprevious resolution in order to produce a significant likelihood ofarriving at a conclusive determination where there was an inconclusivedetermination at the previously lower resolution.

To continue with the working example, step 701 repeats steps 701 through703 with successively finer resolution of 1 arc minute, further dividingthe 10 arc minute tile as illustrated in FIG. 16. The point of interest803(9) in the example is now found within 1 arc minute tile 1601 boundedby the corners located at: 39° 18′ N by 77° 3′ W, 39° 18′ N by 77° 4′ W,39° 19′ N by 77° 4′ W and 39° 19′ N by 77° 3′ W (the desired point ofinterest is 39° 18′ 3.6″ N by 77° 3′ 3.6″ W, and note use of the digitsfrom the arc minutes at an order of magnitude of 1 in the reference ofthe appropriate 1 arc minute tile.) Thus, in FIG. 16, the point ofinterest 803(9) is contained within the ninth 1 arc minute tile (tile1601) from the bottom edge of the 10 arc minute tile and the fourth 1arc minute tile from the right edge of the arc minute tile (as describedpreviously, in the example herein, tiles are referenced from theSoutheast corner(s), which are numerically smallest).

FIG. 17 shows a magnified view of the tile of interest (tile 1601) fromamong all the 1 arc minute tiles nested within the previous 10 arcminute tile 1101. The higher resolution of the 1 arc minute tile isagain compared to the previous 10 arc minute resolution. In this case,however, the entire tile 1601 now appears to lie outside the TV channel43 contour 801 as well as outside the TV channel 44 contour 802.Analysis proceeds, as illustrated by FIG. 18, by plotting exclusiveboundaries at 14.4 km (1801), 8.0 km (1802), 6.0 km (1803), and 0.74 km(1804) around the 1 arc minute tile of interest 1601, similar to theanalysis of step 702 as described previously, to consider possiblevalues for spacing in decreasing order.

At 1 arc minute resolution, the TV channel 44 contour 802 is excluded at14.4 km, (e.g., it is in “white space”) since it is beyond the maximumspacing requirement for any degree of protection with respect to channel44). This is a conclusive result with respect to spacing requirementsfor TV channel 44 and no further analysis at this resolution or higherresolutions is necessary for TV channel 44. This same conclusion is alsoimmediately available for every point on the 1 arc minute tile ofinterest. An analysis of any area within the 1 arc minute tile yieldsthe same result and is determined by the preceding analysis with respectto TV channel 44. Thus, the analysis need only be completed once for aninfinite number of locations with that area. However, TV channel 43contour 801 at distances of 14.4 km, 8.0 km or 6.0 km are not excludedat this point. The 740 m exclusive boundary 1804 is ambiguous, as shownin FIG. 18, so a magnified view of 740 m and 100 m exclusive boundaries1804 and 1805 (not shown in FIG. 18), respectively, is illustrated inFIG. 19. From FIG. 19, the 1 arc minute tile is not excluded at 740 m,but is excluded at 100 m.

Following the example above, the tile of interest might be classifiedusing an inclusive boundary at a spacing distance greater than theexcluded boundary. However, no such inclusive boundary exists for thisspacing at this resolution. The diagonal distance across the 1 arcminute tile at this latitude is approximately 2.34 km (distance inmeters given by degree coordinates varies by latitude in geographiccoordinate systems). Therefore, no single point can be within at most740 m of every point on the 1 minute tile from the definition of theinclusive boundary. Consequently, the nested area analysis of spacing tothe TV channel 44 contour 802 is complete, the tile 1601 for the exampleat this 1 arc minute resolution is classified with respect to TV channel44 contour 802, and analysis continues at a higher resolution for TVchannel 43 contour 801. Therefore, the classification analysis repeatsbased on the decision at step 704 of FIG. D, and nesting analysisadvances to step 701 for TV channel 43 contour 801. The processcontinues similar to the process previously described, but atsuccessively finer resolution of 10 arc seconds.

At a resolution of 10 arc seconds, again, the choice of tile size isselected for convenience using the digits of the arc seconds within adegree at a resolution of 10 arc seconds, yielding an integer index forstoring the nested areas. The increase in resolution from the above 1arc minute tile analysis to the 10 arc second tile analysis is thus 36times finer, and is illustrated in FIG. 20.

The point of interest 803(9) in the working example is now found withina 10 arc second tile N01 bounded by the corners located at: 39° 18′ 0″ Nby 77° 3′ 0″ W, 39° 18′ 0″ N by 77° 3′ 10″ W, 39° 18′ 10″ N by 77° 3′10″ W and 39° 18′ 10″ N by 77° 3′ 0″ W, with the original point ofinterest 803(9) at 39° 18′ 3.6″ N by 77° 3′ 3.6″ W. This 10 arc secondtile 2001 is the first 10 arc second tile from the bottom edge of the 1minute tile 1601 of FIG. J and the first 10 arc second tile from theright edge of the 1 arc minute tile 1601. Again, tiles are referencedfrom the southeast corner(s), which are numerically smallest. Amagnified view of the tile of interest 2001 from among all the 10 arcsecond tiles nested within the previous 1 arc minute tile 1601 is shownin FIG. 21.

As shown in FIG. 22, in a manner analogous to the 1 arc minute tileanalysis, exclusive boundaries are plotted at 14.4 km (2201), 8.0 km(2202), 6.0 km (2203), and 0.74 km (2204) around the tile of interest2001, and the 10 arc second tile 2001 must lie outside the TV channel 43contour C01 (since the new finer resolution tile was fully contained inthe previous coarser resolution tile). At the higher resolution of 10arc second tile, tile 2001 is small relative to the spacing distances,so as to be barely visible in the center of the exclusive boundaries inFIG. 22. Further analysis of TV channel 44 spacing is not required,since the 1 arc minute (lower) resolution classification is also true atthe 10 arc second (higher) resolution (i.e., the TV channel 44 contour802 is beyond 14.4 km from every point in the arc second tile 2001).

In FIG. 22, exclusive boundaries of 14.4 km (2201), 8.0 km (2202), and6.0 km (2203) clearly overlap TV channel 43 contour 801. However, theexclusive boundary 2204 at the 740 m spacing appears ambiguous withrespect to TV channel 43 contour 801. A magnified view of this area withexclusive boundary 2204 is shown in FIG. 23 with exclusive boundaries2204 and 2205 (not shown in FIG. 22) shown at spacings of 740 m and 100m, respectively. As shown in FIG. 23, 740 m exclusive boundary P04barely overlaps TV channel 43 contour C01, while 100 m exclusiveboundary 2205 is clearly outside of TV channel 43 contour 801 for the 10arc second tile 2001.

Therefore, analysis proceeds to consider the inclusive boundaries, asshown in FIG. 24 as inclusive boundary 2401 plotted at 740 m spacing,with plotting illustrated more precisely for maximum distance of 740 m(2402) and less (2403) in FIG. 25. Examination of the inclusive boundarywith respect to the TV channel 43 contour at a spacing distance greaterthan the exclusive boundary conclusion is analogous to the analysis with10 arc minute resolution. Although the method attempts to not overlap acontour with exclusive boundaries at any resolution, inclusive boundaryoverlap might occur to arrive at a conclusion. Since no overlap existswith the appropriate inclusive boundary and TV channel 43 contour 801, aconclusion does not yet exist, and analysis repeats steps 701, 702, and703 at a higher resolution with nested 1 arc second tiles.

The increase in resolution from the above 10 arc second tile 2001analysis to 1 arc second tile of modified is illustrated by partitioningshown in FIG. 26. The point of interest 803(9) is contained within 1 arcsecond tile 2601 bounded by the corners located at: 39° 18′ 3″ N by 77°3′ 3″ W, 39° 18′ 3″ N by 77° 3′ 4″ W, 39° 18′ 4″ N by 77° 3′ 4″ W and39° 18′ 4″ N by 77° 3′ 3″ W, with point of interest 803(9) located at39° 18′ 3.6″ N by 77° 3′ 3.6″ W. This 1 arc second tile 2601 is thefourth 1 arc second tile from the bottom edge of the 10 arc second tile2001 and the fourth 1 arc second tile from the right edge of the 10 arcsecond tile 2001. Again, tiles are referenced from the Southeastcorner(s), which are numerically smallest. A less magnified view of thetile of interest 2601 from among all the 1 second tiles nested withinthe previous 10 arc second tile 2001 is shown in FIG. 27 in order tobring the channel 43 contour in view within the figure.

As before, step 702 analyzes exclusive boundaries 14.4 km (2801), 8.0 km(2802), 6.0 km (2803) and 0.74 km (2804) about the tile of interest 2601with respect to the TV channel contours (e.g., TV channel 43 contour801, with result of analysis of TV channel 44 contour 802 alreadydetermined) as shown in FIG. 28, and with magnified view shown in FIG.29. FIGS. 22 and 28 are similar, but exclusive boundaries are plottedaround the tile of interest. As shown in FIG. 29, the 740 m spacingexclusive boundary 2804 lies outside channel 43 TV contour 801. (notethat the 6.0 km spacing exclusive boundary 2204 of FIG. 22 overlapped TVchannel 43 contour 801). Step 703, for 1 arc second resolution, analyzesinclusive boundary 3001 at 6.0 km (the next spacing up from the largestexclusive boundary found to be completely outside TV channel 43 contour801 of interest), as shown in FIG. 30.

Inclusive boundary 3001 overlaps TV channel 43 contour 801. Theinterpretation of this overlap is as follows: some set of points existinside both TV channel 43 contour 801 and the 6.0 km inclusive boundary3001, for which all such points every point within the 1 arc second tileis at a distance less than 6.0 km from the TV channel 43 contour. Everypoint within the 1 arc second tile of interest 2601 is also greater than740 m from the TV channel 43 contour by the exclusive boundary analysis.Therefore, every point within the 1 arc second tile of interest 2601 isconclusively at a distance between 740 m and 6.0 km from the coveragearea of the protected service. At this point, the method of FIG. Dstops, with areas of all tiles at each resolution classified asavailable or unavailable for operating frequencies and spacing distancesbased on the contours of interest (801 and 802) for TV channels 43 and44.

The previous example of implementing FIG. 7 for the point of interest39.301° N by 77.051° W, which transforms to 39° 18′ 3.6″ N by 77° 3′3.6″ W, might be summarized as follows in Table 7, for exclusion andinclusion results for TV channel 43 and 44 contours, and might besummarized in Table 8 for TVBD operation.

TABLE 7 Area of Analysis Results of Visual Analysis Southeast Channel 43Channel 44 Resolution Reference Max. Exclusion Inclusion Max. ExclusionInclusion  1 degree 39° N Null Null Null Null 77° W 10 minutes 39° 10′ NNull Null  8.0 km Fail 77° 0′ W (14.4 km)  1 minute 39° 18′ N 100 m Fail14.4 km 77° 3′ W (740 m) 10 seconds 39° 18′ 0″ N 100 m Fail 77° 3′ 0″ W(740 m)  1 second 39° 18′ 3″ N 740 m Pass   77° 3′ 3″ W    (6.0 km)Final Result 740 m ≦ Spacing ≦ 6.0 km White Space (>14.4 km) ReferencePoint 39° 18′ 3″ N by 77° 3′ 3″ W 39° 10′ N by 77° 0′ W Resolution ofResult 1 arc second × 1 arc second 1 arc minute × 1 arc minute

TABLE 8 Determination of Permitted TVBD Operation Location (Described byAntenna Height) Latitude Longitude Channel 43 Channel 44 (degrees N)(degrees W) (“Co”/43) (“Adj”/44) (“Adj”/43) (“Co”/44) 39.301 77.051 None10-30 m 10-30 m 10-30 m Final Result None 10-30 m Resolution of Result 1arc second × 1 arc second 1 arc minute × 1 arc minute

Mobile Remote Device Considerations

As shown in FIG. 1, remote device 114 might communicate wirelessly withWS channel allocation system 100, implying that remote device 114 mightbe mobile. In such cases, remote device 114 might generate a series ofqueries as remote device 114 moves across a region in a geographic area.For example, a TVBD might move from one physical location to anotherwith or without continuously transmitting data (e.g., a laptopcomputer). The TVBD queries the WS channel allocation system each timethe TVBD moves from one physical location to another. An example of animplementation of the concept of movement is given by the regulatoryrequirement to query upon change in position of 100 m as described inparagraph 113 in the FCC “Second Memorandum Opinion and Order.”Therefore, for some embodiments herein, the WS channel allocation systememploys 1 Arc Second white space mappings for channel allocation, and 3Arc Second×3 Arc Second mobile device queries. For such embodiments, inaddition to transmitting the channel list for the given 1 Arc Secondtile having the TVBD, a response to a query also provides the channellists for the tiles around the given 1 Arc Second tile.

FIG. 31 illustrates mobile device 3101 receiving channel allocations inan area 3100 for its own tile and surrounding tiles in a manner asdescribed above. Area 3100 is divided into tiles of lowest resolution(e.g., 1 arc second tiles) and fully classified with channels eitheravailable or unavailable. As shown in FIG. 31, tiles are referenced bytheir row-column designations (i.e., tile (3,4) is the tile at row 3,column 4 of FIG. 31). Mobile device 3101 requests and receives whitespace channel allocation for tile (2,4), but also receives channelallocation information in the 3 Arc Second by 3 Arc Second areaincluding this tile at its center. Consequently, mobile device 3101 alsoreceives available channel information or channel lists for tiles (1,3),(1,4), (1,5), (2,3), (2,5), (3,3) (3,4), and (3,5).

In addition, embodiments of the present invention might track velocity,direction and even acceleration of mobile device 3101 through locationinformation. From such tracking information, vector 3102 might bederived and employed to estimate or otherwise predict future reached 1arc second tiles in a predicted path of mobile device 3101, shown astiles (2,5), (1,5), and (0,6). While channels allocations for tiles(2,5) and (1,5) will be downloaded to mobile device 3101 as describedwhen receiving channel allocation for tile (2,4), embodiments of thepresent invention might begin searching tile (0,6) for availablechannels to increase processing speed as mobile device 3101 moves towardtile (2,5).

Self-Contained Wireless Networking Device Channel Allocation

Rather than obtain channel allocations from a remote database, someembodiments of the present invention might access a database to obtainprotected service or other registered user communication characteristicinformation and directly determine channel lists of available channelsfor communication for itself. FIG. 32 shows an exemplary embodiment of asystem 3200 with a self-contained networking device (SCND) 3214determining its channel allocation. SCND 3214 is coupled to network3212, which might be the Internet, and communicates with database 3210,which might be a database of protected service or other registered usercommunication characteristic information. SCND 3214 includes i) wirelessnetwork communication interface 3215 to enable communications withvarious wireless devices near and in communication with SCND 3214; ii)network communication interface 3216 to enable communications withnetwork 3212 and database 3210; iii) processor 3217 to form messages,enable communications, control channel allocation and otherwise enablefunctions of SCND 3214; and iv) location module 3218, such as a globalpositioning system (GPS) module, to determine a geographic location ofSCND 3214 about the Earth. Processor 3217 represents processor functionsincluding memory or storage that enable execution of a white spaceallocation similar to that describes previously. Processor 3217,wireless network communication interface 3215, and location module 3218might also be employed to generate messaging to wireless devices tomeasure channel characteristics to determine a geographic location ofradio coverage 3220 of SCND 3214 about its location.

FIG. 33 shows an exemplary method as might be employed by theself-contained networking device of FIG. 32. At step 3302, processor3217 determines it geographic location from location module 3218. Atstep 3304, processor 3217 causes communication with database 3210through network communication interface 3216 to receive communicationcharacteristic information about its location. At step 3306, processor3217 determines an initial tile over its geographic area based on arelative maximum operating range (which might also include interferencefrom wireless devices located at the outside of the coverage area of theSCND). At step 3308, processor 3217 determines channel availability forclassified tiles of successive resolution within the initial tile andabout SCND 3214. At step 3310, processor 3217 determines locations ofvarious wireless devices near and/or associated with SCND 3214 by, forexample, query of the devices. At step 3312, processor 3217 determineschannel allocation lists about SCND 3214 for various wireless devicesusing their location information through an iterative search of theclassified tiles of successive resolution within the initial tile. Atstep 3314, processor 3217, through wireless network communicationinterface 3215, communicates the channel allocation lists to thecorresponding wireless devices associated with SCND 3214.

Message Insertion and Supplemental Content Delivery

In some embodiments of the present invention, a WS channel allocationsystem might also allow services to obtain identification or other userinformation of, for example, TVBD users registered with the WS channelallocation system, and then receive message insertion (MI) informationfrom the service for transmission to the TVBD. MI information from theservice might identify locations (e.g., servers) having advertising,broadcast or other supplemental content of interest to the TVBD user,and allow the TVBD to formulate requests for such content. The WSchannel allocation system might also register these other supplementalcontent services within its database, providing for secure communicationand user-information security, while billing the supplemental contentservices for such features of the system.

FIG. 34 shows an exemplary configuration 3400 for white space (WS)channel allocation system 100 (FIG. 1) providing for message insertion,such as advertising content, for TVBD 3402 in communication with WSchannel allocation system 100 through network (e.g., the Internet) 3404.Message-Insertion (MI) Server 3406 is in communication with WS channelallocation system 100, and WS channel allocation system 100 mightfurther include a MI registration module 3401 for coordinatingcommunication with MI Server 3406. Through network 3404, TVBD 3402 mightbe in communication with at least one of Web Server 3408 and BroadcastServer 3410.

MI Server 3406 communicates with MI registration module 3401 forregistering the MI server in WS channel allocation system 100 for i)security and secure communication with system 100; ii) receiving TVBD orother unprotected service MI-type information (such as, for example,location-specific advertising, user-type sales information,location-specific alarm information, and the like) that MI Server 3406desires to communicate to TVBD or other unprotected service devices (andthus, device users); and billing and other financial information.Consequently, MI Server 3406 receives TVBD_ID_INFO including user ID andtype (e.g., location information) for TVBD 3402 and providesADDR_ID_INFO including MI-type information (e.g., Web or BroadcastServer IP address information associated with TVBD_ID_INFO) to system100 for transfer to TVBD 3402. Alternatively, aliased or anonymized suchinformation for TVBD_ID_INFO might be used to protect user privacy.

WS channel allocation system 100 reformats and transmits to TVBD 3402the MI-type information to TVBD 3402 as MI_Mess channel input data. Notethat TVBD 3402 communicates through WS_Mess channel with WS channelallocation system 100, as described previously, for TVBD registration,keep-alive transmissions, and periodic update information including TVBDlocation and channel lists. Given received ADDR_ID_INFO identifying, forexample, IP addresses for Web Server 3408 and/or Broadcast Server 3410coupled to Network 3404 that might be displayed to the TVBD user, TVBD3402 initiates communication with at least one of Web Server 3408 andBroadcast Server 3410 through a Content_Mess channel through Network3404. TVBD 3402 then receives web page or broadcast information from atleast one of Web Server 3408 and Broadcast Server 3410 through theContent_Mess channel through Network 3404. For example, TVBD 3402Content_Mess channel might provide Web_Request to request a Web pagedefined by ADDR_ID_INFO, or Broadcast_Request to request broadcastinformation (e.g., radio channel or alerts) defined by ADDR_ID_INFO.Based on these messages, the corresponding Web page (as Web_Content) orbroadcast information (as Broadcast_Content) is transmitted back to TVBD3402 through Network 3404 in the Content_Mess channel.

A channel allocation system operating in accordance with one or moreembodiments of the present invention might provide for the followingadvantages. The channel allocation system provides a data repository,data registration process, and query process as defined by, for example,the FCC to provide allocation and assignment of white space channels inthe TV spectrum. Such allocation provides such services withoutinterference to protected users, while expanding the number of channelsavailable to existing and new wireless-based services. Such services,in-turn, benefit from transmission through spectrum with propagationcharacteristics that allow devices to provide service at greaterdistance ranges, reduced transmit power, and higher speed than existingunlicensed devices. Service providers can generate white space or otherchannel information relatively quickly, requiring significantly reducedserver computation time when responding to a query by a device, in orderto reduce cost and improve efficiency of providing the service.

Reference herein to “one embodiment” or “an embodiment” means that aparticular feature, structure, or characteristic described in connectionwith the embodiment can be included in at least one embodiment of theinvention. The appearances of the phrase “in one embodiment” in variousplaces in the specification are not necessarily all referring to thesame embodiment, nor are separate or alternative embodiments necessarilymutually exclusive of other embodiments. The same applies to the term“implementation.”

As used in this application, the word “exemplary” is used herein to meanserving as an example, instance, or illustration. Any aspect or designdescribed herein as “exemplary” is not necessarily to be construed aspreferred or advantageous over other aspects or designs. Rather, use ofthe word exemplary is intended to present concepts in a concretefashion.

Additionally, the term “or” is intended to mean an inclusive “or” ratherthan an exclusive “or”. That is, unless specified otherwise, or clearfrom context, “X employs A or B” is intended to mean any of the naturalinclusive permutations. That is, if X employs A; X employs B; or Xemploys both A and B, then “X employs A or B” is satisfied under any ofthe foregoing instances. In addition, the articles “a” and “an” as usedin this application and the appended claims should generally beconstrued to mean “one or more” unless specified otherwise or clear fromcontext to be directed to a singular form.

Moreover, the terms “system,” “component,” “module,” “interface,”,“model” or the like are generally intended to refer to acomputer-related entity, either hardware, a combination of hardware andsoftware, software, or software in execution. For example, a componentmay be, but is not limited to being, a process running on a processor, aprocessor, an object, an executable, a thread of execution, a program,and/or a computer. By way of illustration, both an application runningon a controller and the controller can be a component. One or morecomponents may reside within a process and/or thread of execution and acomponent may be localized on one computer and/or distributed betweentwo or more computers.

Although the subject matter described herein may be described in thecontext of illustrative implementations to process one or more computingapplication features/operations for a computing application havinguser-interactive components the subject matter is not limited to theseparticular embodiments. Rather, the techniques described herein can beapplied to any suitable type of user-interactive component executionmanagement methods, systems, platforms, and/or apparatus.

The present invention may be implemented as circuit-based processes,including possible implementation as a single integrated circuit (suchas an ASIC or an FPGA), a multi-chip module, a single card, or amulti-card circuit pack. As would be apparent to one skilled in the art,various functions of circuit elements may also be implemented asprocessing blocks in a software program. Such software may be employedin, for example, a digital signal processor, micro-controller, orgeneral-purpose computer.

The present invention can be embodied in the form of methods andapparatuses for practicing those methods. The present invention can alsobe embodied in the form of program code embodied in tangible media, suchas magnetic recording media, optical recording media, solid statememory, floppy diskettes, CD-ROMs, hard drives, or any othermachine-readable storage medium, wherein, when the program code isloaded into and executed by a machine, such as a computer, the machinebecomes an apparatus for practicing the invention. The present inventioncan also be embodied in the form of program code, for example, whetherstored in a storage medium, loaded into and/or executed by a machine, ortransmitted over some transmission medium or carrier, such as overelectrical wiring or cabling, through fiber optics, or viaelectromagnetic radiation, wherein, when the program code is loaded intoand executed by a machine, such as a computer, the machine becomes anapparatus for practicing the invention. When implemented on ageneral-purpose processor, the program code segments combine with theprocessor to provide a unique device that operates analogously tospecific logic circuits. The present invention can also be embodied inthe form of a bitstream or other sequence of signal values electricallyor optically transmitted through a medium, stored magnetic-fieldvariations in a magnetic recording medium, etc., generated using amethod and/or an apparatus of the present invention.

Unless explicitly stated otherwise, each numerical value and rangeshould be interpreted as being approximate as if the word “about” or“approximately” preceded the value of the value or range.

It should be understood that the steps of the exemplary methods setforth herein are not necessarily required to be performed in the orderdescribed, and the order of the steps of such methods should beunderstood to be merely exemplary. Likewise, additional steps may beincluded in such methods, and certain steps may be omitted or combined,in methods consistent with various embodiments of the present invention.Consequently, although the elements in the following method claims, ifany, are recited in a particular sequence with corresponding labeling,unless the claim recitations otherwise imply a particular sequence forimplementing some or all of those elements, those elements are notnecessarily intended to be limited to being implemented in thatparticular sequence.

As used herein in reference to an element and a standard, the term“compatible” means that the element communicates with other elements ina manner wholly or partially specified by the standard, and would berecognized by other elements as sufficiently capable of communicatingwith the other elements in the manner specified by the standard. Thecompatible element does not need to operate internally in a mannerspecified by the standard.

Also for purposes of this description, the terms “couple,” “coupling,”“coupled,” “connect,” “connecting,” or “connected” refer to any mannerknown in the art or later developed in which energy is allowed to betransferred between two or more elements, and the interposition of oneor more additional elements is contemplated, although not required.Conversely, the terms “directly coupled,” “directly connected,” etc.,imply the absence of such additional elements.

It will be further understood that various changes in the details,materials, and arrangements of the parts which have been described andillustrated in order to explain the nature of this invention may be madeby those skilled in the art without departing from the scope of theinvention as expressed in the following claims.

I claim:
 1. A method of allocating communication channels within ageographic area having protected classes of service, the methodcomprising: generating, based on communications characteristics fromstorage, protected service contours over the geographic area for one ormore of the protected classes of service; partitioning a region over thegeographic area into unclassified tiles at a first level of resolution;classifying, by a processor, each unclassified tile, if able, foravailability of channels with respect to each protected service contourof the region associated with the tile at the first level of resolution;and if the corresponding unclassified tile is not classified, dividingeach unclassified tile into nested tiles of one or more subsequentlevels of finer resolution, and forming nested, classified tiles ofsuccessive levels of resolution by classifying, if able, each tile atthe subsequent level of finer resolution with respect to each protectedservice contour of the region associated with the corresponding tile atthe subsequent level.
 2. The method of allocating communication channelsas recited in claim 1, wherein, if the corresponding unclassified tileis not classified, comprising: for each unclassified tile at a currentlevel of resolution: (a) nested partitioning of the unclassified tile atthe current level of resolution into tiles at a successive level offiner resolution; (b) classifying, if able, each tile at the successivelevel of finer resolution based upon availability of channels withrespect to each corresponding protected service contour of the region;(c) further classifying, if able, each unclassified tile at thesuccessive level of finer resolution with respect to each correspondingprotected service contour of the region and at least one of an exclusiveboundary and an inclusive boundary of the unclassified tile at thesuccessive level of finer resolution; and (d) repeating (a) through (c)at successive, finer levels of resolution until specifying channelavailability of the region with nested, classified tiles of successivelevels of resolution.
 3. The method of claim 1, further comprising:receiving, from a device, a query having a location and one or moredesired channels of operation corresponding to the query location;identifying, beginning with the first level and searching successivelevels of the nested, classified tiles of successive levels ofresolution, a classified tile classified as available for the querylocation based on the one or more desired channels of operation; andallocating channels, if available, associated with the identified,classified tile with the query location to a channel list.
 4. The methodof claim 3, further comprising transmitting the channel list to thedevice.
 5. The method of claim 4, wherein for the transmitting of thechannel list to the device, the device belongs to an unprotected classof service.
 6. The method of claim 4, wherein for the transmitting ofthe channel list to the device, the device is at least one of i) atelevision band device (TVBD) of a white space channel allocation systemand ii) a wireless handset of a femtocell communication system.
 7. Themethod of claim 4, wherein for the transmitting of the channel list tothe device, the device is a mobile device and the method furthercomprises transmitting channel lists for tiles adjacent to theidentified, classified tile.
 8. The method of claim 7, wherein for thetransmitting of the channel list to the device, the identified,classified tile is a one arc-second tile and the method comprisestransmitting channel lists for one arc-second tiles adjacent to theidentified, classified tile.
 9. The method of claim 4, furthercomprising registering a new protected service, and updating the nested,classified tiles of successive levels of resolution for one or morecontours of the new protected service.
 10. The method of claim 9,further comprising updating the channel list for the device, andtransmitting the updated channel list to the device.
 11. The method ofclaim 3, wherein the partitioning the region comprises translatinggeographic coordinates, and wherein the method further comprises formingan addressing scheme for the nested, classified tiles of successivelevels of resolution based on the translated geographic coordinates;associating the query location with a corresponding point in thetranslated geographic coordinates of the addressing scheme; andsearching the nested, classified tiles of successive levels ofresolution based on the translated geographic coordinates of a pointcorresponding to the query location.
 12. The method of claim 1, whereinthe classifying each tile at a level of resolution comprises: verifyingprotected service requirements for a corresponding protected servicecontour; and storing data, based on the verifying of the protectedservice requirements, of whether corresponding channels of the tile areavailable or unavailable.
 13. The method of claim 1, wherein theclassifying, if able, each unclassified tile at the subsequent level offiner resolution comprises: forming an exclusive boundary area for eachexclusive boundary outside a perimeter of the tile, the exclusiveboundary defined by a spacing distance; verifying, for the exclusiveboundary area, protected service requirements for each correspondingprotected service contour; and storing, based on the verifying of theprotected service requirements for the exclusive boundary area,availability of corresponding channels of the tile.
 14. The invention ofclaim 13, wherein, for the forming of the exclusive boundary area, eachspacing distance corresponds to a protected distance from anon-protected service class transmitter.
 15. The method of claim 1,wherein the classifying, if able, of each unclassified tile at thesubsequent level of finer resolution comprises: forming an inclusiveboundary area for each inclusive boundary inside a perimeter of thetile, the inclusive boundary defined by a corresponding spacingdistance; verifying, for the inclusive boundary area, protected servicerequirements for each corresponding protected service contour; andstoring, based on the verifying of the protected service requirementsfor the inclusive boundary area, availability of corresponding channelsof the tile.
 16. The method of claim 15, wherein, for the forming theinclusive boundary area, the corresponding spacing distance is a maximumspacing distance for an exclusive boundary.
 17. The method of claim 1,wherein the generating the protected service contours comprises forminga protected area with a polygon.
 18. The method of claim 17, wherein theforming the protected area comprises: defining the protected area by Ngeographic points from 0 to 359 degrees at M azimuths from 0 to 359degrees from a center emitter, where N and M are positive integers;connecting lines are drawn in a Cartesian plane of latitudes orlongitudes between adjacent geographic points; combining sample pointswith linear interpolation into a contour about the protected area over asurface area on an ellipsoidal (geodetic) model of the Earth's surface.19. The method of claim 17, further comprising allocating white spacecommunication channels to one or more unprotected classes of service,wherein the plurality of protected classes of service includes TVbroadcast stations, and the one or more unprotected classes of serviceincludes TV band devices (TVBDs).
 20. The method of claim 19, whereinthe allocating of white space communication channels comprises:receiving, from a TVBD, a query having a location and one or moredesired channels of operation corresponding to the query location;identifying, beginning with the first level and searching successivelevels of the nested, classified tiles of successive levels ofresolution, a classified tile classified as available with the querylocation based on the one or more desired channels of operation;allocating, if available, white space channels associated with theidentified, classified tile with the query location to channel list; andtransmitting the channel list to the TVBD.
 21. The method of claim 1,wherein the partitioning the region comprises translating geographiccoordinates, and wherein the method further comprises forming anaddressing scheme for the nested, classified tiles of successive levelsof resolution based on the translated geographic coordinates.
 22. Themethod of claim 1, further comprising: receiving a message from a newprotected service class device, the message including communicationcharacteristics for the new protected service class device; generating anew protected service contour based on the communication characteristicsfor the new protected service class device; and updating the nested,classified tiles of successive levels of resolution based on the newprotected service contour.
 23. A machine-readable, non-transitory,storage medium, having encoded thereon program code, wherein, when theprogram code is executed by a machine, the machine implements a methodfor allocating communication channels within a geographic area havingprotected classes of service, comprising the steps of: generating, basedon communications characteristics from storage, protected servicecontours over the geographic area for one or more of the protectedclasses of service; partitioning a region over the geographic area intounclassified tiles at a first level of resolution; classifying eachunclassified tile, if able, for availability of channels with respect toeach protected service contour of the region associated with the tile atthe first level of resolution; and if the corresponding unclassifiedtile is not classified, dividing each unclassified tile into nestedtiles of one or more subsequent levels of finer resolution, and formingnested, classified tiles of successive levels of resolution byclassifying, if able, each tile at the subsequent level of finerresolution with respect to each protected service contour of the regionassociated with the corresponding tile at the subsequent level.
 24. Themachine-readable, non-transitory, storage medium as recited in claim 23,wherein, if the corresponding unclassified tile is not classified,comprising the steps of: for each unclassified tile at a current levelof resolution: (a) nested partitioning of the unclassified tile at thecurrent level of resolution into tiles at a successive level of finerresolution; (b) classifying, if able, each tile at the successive levelof finer resolution based upon availability of channels with respect toeach corresponding protected service contour of the region; (c) furtherclassifying, if able, each unclassified tile at the successive level offiner resolution with respect to each corresponding protected servicecontour of the region and at least one of an exclusive boundary and aninclusive boundary of the unclassified tile at the successive level offiner resolution; and (d) repeating (a) through (c) at successive, finerlevels of resolution until specifying channel availability of the regionwith nested, classified tiles of successive levels of resolution. 25.Apparatus for allocating communication channels within a geographic areahaving protected classes of service, comprising: a database interfaceconfigured to retrieve communications characteristics for the pluralityof protected classes of service from a database, the database furtherincluding i) communications characteristics for a plurality of protectedclasses of service, and ii) registration information for one or moredevices belonging to one or more classes of unprotected service; aprocessor configured to i) generate, based on communicationscharacteristics from the database, protected service contours over thegeographic area for one or more of the protected classes of service, ii)partition a region over the geographic area into unclassified tiles at afirst level of resolution, and classify each unclassified tile, if able,for availability of channels with respect to each protected servicecontour of the region associated with the tile at the first level ofresolution, wherein, if the corresponding unclassified tile is notclassified, the processor is further configured to: i) divide eachunclassified tile into nested tiles of one or more subsequent levels offiner resolution, and ii) form nested, classified tiles of successivelevels of resolution by classifying, if able, each tile at thesubsequent level of finer resolution with respect to each protectedservice contour of the region associated with the corresponding tile atthe subsequent level; and wherein the processor stores the nested,classified tiles of successive levels of resolution in the database. 26.The apparatus as recited in claim 25, wherein, if the correspondingunclassified tile is not classified, the processor, for eachunclassified tile at a current level of resolution, is furtherconfigured to: (a) nested partition the unclassified tile at the currentlevel of resolution into tiles at a successive level of finerresolution; (b) classify, if able, each tile at the successive level offiner resolution based upon availability of channels with respect toeach corresponding protected service contour of the region; (c) furtherclassify, if able, each unclassified tile at the successive level offiner resolution with respect to each corresponding protected servicecontour of the region and at least one of an exclusive boundary and aninclusive boundary of the unclassified tile at the successive level offiner resolution; and (d) repeat (a) through (c) at successive, finerlevels of resolution until specifying channel availability of the regionwith nested, classified tiles of successive levels of resolution.